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WorksheetsCCNA Practice Quiz
Total questions: 100
Worksheet time: 2hrs 40mins
1. What are two benefits of network automation? (Choose two)
A. reduced operational costs
B. reduced hardware footprint
C. faster changes with more reliable results
D. fewer network failures
E. increased network security
2. Which command enables a router to become a DHCP client?
A. ip address dhcp
B. ip helper-address
C. ip dhcp pool
D. ip dhcp client
3. Which design element is a best practice when deploying an 802.11b wireless infrastructure?
A. disabling TPC so that access points can negotiate signal levels with their attached wireless devices
▪ B. setting the maximum data rate to 54 Mbps on the Cisco Wireless LAN Controller
C. allocating nonoverlapping channels to access points that are in close physical proximity to one another
D. configuring access points to provide clients with a maximum of 5 Mbps
4. When configuring IPv6 on an interface, which two IPv6 multicast groups are joined? (Choose two)
A. 2000::/3
B. 2002::5
C. FC00::/7
D. FF02::1
E. FF02::2
5. Which option about JSON is true?
A. uses predefined tags or angle brackets (<>) to delimit markup text
B. used to describe structured data that includes arrays
C. used for storing information
D. similar to HTML, it is more verbose than XML
6. Which IPv6 address type provides communication between subnets and cannot route on the Internet?
A. global unicast
B. unique local
C. link-local
D. multicast
7. Which command prevents passwords from being stored in the configuration as plaintext on a router or switch?
A. enable secret
B. service password-encryption
C. username Cisco password encrypt
D. enable password
8. What are two southbound APIs? (Choose two )
A. OpenFlow
B. NETCONF
C. Thrift
D. CORBA
E. DSC
9. Which set of action satisfy the requirement for multifactor authentication?
A. The user swipes a key fob, then clicks through an email link.
B. The user enters a user name and password, and then clicks a notification in an authentication app on a mobile device.
C. The user enters a PIN into an RSA token, and then enters the displayed RSA key on a login screen.
D. The user enters a user name and password and then re-enters the credentials on a second screen.
10. Which two capacities of Cisco DNA Center make it more extensible? (Choose two)
A. adapters that support all families of Cisco IOS software
B. SDKs that support interaction with third-party network equipment
C. customized versions for small, medium, and large enterprises
D. REST APIs that allow for external applications to interact natively with Cisco DNA Center
E. modular design that is upgradable as needed
11. An email user has been lured into clicking a link in an email sent by their company’s security organization. The webpage that opens reports that it was safe but the link could have contained malicious code. Which type of security program is in place?
A. Physical access control
B. Social engineering attack
C. brute force attack
D. user awareness
12. Which type of wireless encryption is used for WPA2 in pre-shared key mode?
A. TKIP with RC4
B. RC4
C. AES-128
D. AES-256
13. Which two must be met before SSH can operate normally on a Cisco IOS switch? (Choose two)
A. The switch must be running a k9 (crypto) IOS image.
B. The ip domain-name command must be configured on the switch.
C. IP routing must be enabled on the switch.
D. A console password must be configured on the switch.
E. Telnet must be disabled on the switch.
14. Which type of address is the public IP address of a NAT device?
A. outside global
B. outsdwde local
C. inside global
D. insride local
E. outside public
15. Refer to the exhibit. Which prefix does Router 1 use for traffic to Host A?
A. 10.10.10.0/28
B. 10.10.13.0/25
C. 10.10.13.144/28
D. 10.10.13.208/29
16. How does HSRP provide first hop redundancy?
A. It load-balances traffic by assigning the same metric value to more than one route to the same destination m the IP routing table.
B. It load-balances Layer 2 traffic along the path by flooding traffic out all interfaces configured with the same VLAN.
C. It forwards multiple packets to the same destination over different routed links n the data path.
D. It uses a shared virtual MAC and a virtual IP address to a group of routers that serve as the default gateway for hosts on a LAN.
17. In Which way does a spine-and-leaf architecture allow for scalability in a network when additional access ports are required?
A. A spine switch and a leaf switch can be added with redundant connections between them.
B. A spine switch can be added with at least 40 GB uplinks.
C. A leaf switch can be added with a single connection to a core spine switch.
D. A leaf switch can be added with connections to every spine switch.
18. Which two actions are performed by the Weighted Random Early Detection mechanism? (Choose two)
A. It drops lower-priority packets before it drops higher-priority packets.
B. It can identify different flows with a high level of granularity.
C. It guarantees the delivery of high-priority packets.
D. It can mitigate congestion by preventing the queue from filling up.
E. It supports protocol discovery.
19. A network engineer must back up 20 network router configurations globally within a customer environment. Which protocol allows the engineer to perform this function using the Cisco IOS MIB?
A. CDP
B. SNMP
C. SMTP
D. ARP
20. Refer to the exhibit. What is the effect of this configuration?
A. The switch port interface trust state becomes untrusted.
B. The switch port remains administratively down until the interface is connected to another switch.
C. Dynamic ARP inspection is disabled because the ARP ACL is missing.
D. The switch port remains down until it is configured to trust or untrust incoming packets.
21. A frame that enters a switch fails the Frame Check Sequence. Which two interface counters are incremented? (Choose two)
A. runts
B. giants
C. frame
D. CRC
E. input errors
22. How do TCP and UDP differ in the way that they establish a connection between two endpoints?
A. TCP uses synchronization packets, and UDP uses acknowledgment packets.
B. UDP uses SYN, SYN ACK and FIN bits in the frame header while TCP uses SYN, SYN ACK and ACK bits.
C. UDP provides reliable message transfer and TCP is a connectionless protocol.
D. TCP uses the three-way handshake and UDP does not guarantee message delivery.
23. When OSPF learns multiple paths to a network, how does it select a route?
A. It multiple the active K value by 256 to calculate the route with the lowest metric.
B. For each existing interface, it adds the metric from the source router to the destination to calculate the route with the lowest bandwidth.
C. It divides a reference bandwidth of 100 Mbps by the actual bandwidth of the existing interface to calculate the router with the lowest cost.
D. It count the number of hops between the source router and the destination to determine the router with the lowest metric.
24. Refer to the exhibit. Which password must an engineer use to enter the enable mode?
A. adminadmin123
B. default
C. testing1234
D. cisco123
25. Which configuration is needed to generate an RSA key for SSH on a router?
A. Configure the version of SSH.
B. Configure VTY access.
C. Create a user with a password.
D. Assign a DNS domain name.
26. Which output displays a JSON data representation?
A. Option A
B. Option B
C. Option C
D. Option D
27. What is the primary different between AAA authentication and authorization?
A. Authentication verifies a username and password, and authorization handles the communication between the authentication agent and the user database.
B. Authentication identifies a user who is attempting to access a system, and authorization validates the users password.
C. Authentication identifies and verifies a user who is attempting to access a system, and authorization controls the tasks the user can perform.
D. Authentication controls the system processes a user can access and authorization logs the activities the user initiates.
28. A Cisco IP phone receive untagged data traffic from an attached PC. Which action is taken by the phone?
A. It allows the traffic to pass through unchanged.
B. It drops the traffic.
C. It tags the traffic with the default VLAN.
D. It tags the traffic with the native VLAN.
29. An engineer must configure a/30 subnet between two routers. Which usable IP address and subnet mask combination meets this criteria?
A. interface e0/0 description to HQ-A370:98968 ip address 10.2.1.3 255.255.255.252
B. interface e0/0 description to HQ-A370:98968 ip address 192.168.1.1 255.255.255.248
C. interface e0/0 description to HQ-A370:98968 ip address 172.16.1.4 255.255.255.248
D. interface e0/0 description to HQ-A370:98968 ip address 209.165.201.2 255.255.255.252
30. What is a benefit of using a Cisco Wireless LAN Controller?
A. Central AP management requires more complex configurations.
B. Unique SSIDs cannot use the same authentication method.
C. It supports autonomous and lightweight APs.
D. It eliminates the need to configure each access point individually.
31. What are two characteristics of a controller-based network? (Choose two)
A. The administrator can make configuration updates from the CLI.
B. It uses northbound and southbound APIs to communicate between architectural layers.
C. It moves the control plane to a central point.
D. It decentralizes the control plane, which allows each device to make its own forwarding decisions.
E. It uses Telnet to report system issues.
32. Which attribute does a router use to select the best path when two or more different routes to the same destination exist from two different routing protocols?
A. dual algorithm
B. metric
C. administrative distance
D. hop count
33. Refer to Exhibit. How does SW2 interact with other switches in this VTP domain?
A. It processes VTP updates from any VTP clients on the network on its access ports.
B. It receives updates from all VTP servers and forwards all locally configured VLANs out all trunk ports.
C. It forwards only the VTP advertisements that it receives on its trunk ports.
D. It transmits and processes VTP updates from any VTP Clients on the network on its trunk ports.
34. Which unified access point mode continues to serve wireless clients after losing connectivity to the Cisco Wireless LAN Controller?
A. sniffer
B. mesh
C. flexconnect
D. local
35. Which two encoding methods are supported by REST APIs? (Choose two)
A. YAML
B. JSON
C. EBCDIC
D. SGML
E. XML
36. What are two reasons that cause late collisions to increment on an Ethernet interface? (Choose two)
A. when the sending device waits 15 seconds before sending the frame again
B. when the cable length limits are exceeded
C. when one side of the connection is configured for half-duplex
D. when Carriner Sense Multiple Access/Collision Detection is used
D. when Carriner Sense Multiple Access/Collision Detection is used
37. Router A learns the same route from two different neighbors, one of the neighbor routers is an OSPF neighbor and the other is an EIGRP neighbor. What is the administrative distance of the route that will be installed in the routing table?
A. 20
B. 90
C. 110
D. 115
38. What is the primary effect of the spanning-tree portfast command?
A. It enables BPDU messages
B. It minimizes spanning-tree convergence time
C. It immediately puts the port into the forwarding state when the switch is reloaded
D. It immediately enables the port in the listening state
39. What is the default behavior of a Layer 2 switch when a frame with an unknown destination MAC address is received?
A. The Layer 2 switch drops the received frame.
B. The Layer 2 switch floods packets to all ports except the receiving port in the given VLAN.
C. The Layer 2 switch sends a copy of a packet to CPU for destination MAC address learning.
D. The Layer 2 switch forwards the packet and adds the destination MAC address to its MAC address table.
40. Refer to the exhibit. What is the effect of this configuration?
A. All ARP packets are dropped by the switch.
B. Egress traffic is passed only if the destination is a DHCP server.
C. All ingress and egress traffic is dropped because the interface is untrusted.
D. The switch discard all ingress ARP traffic with invalid MAC-to-IP address bindings.
41. Refer to the exhibit. An engineer configured NAT translations and has verified that the configuration is correct. Which IP address is the source IP?
A. 10.4.4.4
B. 10.4.4.5
C. 172.23.103.10
D. 172.23.104.4
42. Refer to the exhibit. Which route does R1 select for traffic that is destined to 192 168.16.2?
A. 192.168.16.0/21
B. 192.168.16.0/24
C. 192.168 26.0/26
D. 192.168.16.0/27
43. Which IPv6 address block sends packets to a group address rather than a single address?
A. 2000::/3
B. FC00::/7
C. FE80::/10
D. FF00::/8
44. Which two values or settings must be entered when configuring a new WLAN in the Cisco Wireless LAN Controller GUI? (Choose two)
A. management interface settings
B. QoS settings
C. Ip address of one or more access points
D. SSID
E. Profile name
45. Which two actions influence the EIGRP route selection process? (Choose two)
A. The router calculates the reported distance by multiplying the delay on the exiting Interface by 256.
B. The router calculates the best backup path to the destination route and assigns it as the feasible successor.
C. The router calculates the feasible distance of all paths to the destination route.
D. The advertised distance is calculated by a downstream neighbor to inform the local router of the bandwidth on the link.
E. The router must use the advertised distance as the metric for any given route.
46. Refer to Exhibit. Which action do the switches take on the trunk link?
A. The trunk does not form and the ports go into an err-disabled status.
B. The trunk forms but the mismatched native VLANs are merged into a single broadcast domain.
C. The trunk does not form, but VLAN 99 and VLAN 999 are allowed to traverse the link.
D. The trunk forms but VLAN 99 and VLAN 999 are in a shutdown state.
47. Which command is used to specify the delay time in seconds for LLDP to initialize on any interface?
A. lldp timer
B. lldp holdtimt
C. lldp reinit
D. lldp tlv-select
48. An engineer configured an OSPF neighbor as a designated router. Which state verifies the designated router is in the proper mode?
A. Exchange
B. 2-way
C. Full
D. Init
49. An office has 8 floors with approximately 30-40 users per floor What command must be configured on the router Switched Virtual Interface to use address space efficiently?
A. ip address 192.168.0.0 255.255.0.0
B. ip address 192.168.0.0 255.255.254.0
C. ip address 192.168.0.0 255.255.255.128
D. ip address 192.168.0.0 255.255.255.224
50. Which device performs stateful inspection of traffic?
A. firewall
B. switch
C. access point
D. wireless controller
51. What criteria is used first during the root port selection process?
A. local port ID
B. lowest path cost to the root bridge
C. lowest neighbor’s bridge ID
D. lowest neighbor’s port ID
52. Router R2 is configured with multiple routes to reach network 10 1.1.0/24 from router R1. What protocol is chosen by router R2 to reach the destination network 10.1.1.0/24?
A. eBGP
B. static
C. OSPF
D. EIGRP
53. A network administrator enabled port security on a switch interface connected to a printer. What is the next configuration action in order to allow the port to learn the MAC address of the printer and insert it into the table automatically?
A. enable dynamic MAC address learning
B. implement static MAC addressing.
C. enable sticky MAC addressing
D. implement auto MAC address learning
54. Which configuration ensures that the switch is always the root for VLAN 750?
A. Switch(config)#spanning-tree vlan 750 priority 38003685
B. Switch(config)#spanning-tree vlan 750 root primary
C. Switch(config)#spanning-tree vlan 750 priority 614440
D. Switch(config)#spanning-tree vlan 750 priority 0
55. An engineer must configure an OSPF neighbor relationship between router R1 and R3 The authentication configuration has been configured and the connecting interfaces are in the same 192.168 1.0/30 sublet. What are the next two steps to complete the configuration? (Choose two.)
A. configure the hello and dead timers to match on both sides
B. configure the same process ID for the router OSPF process
C. configure the same router ID on both routing processes
E. configure both interfaces with the same area ID
56. What protocol allows an engineer to back up 20 network router configurations globally while using the copy function?
A. SMTP
B. SNMP
C. TCP
D. FTP
57. Which state does the switch port move to when PortFast is enabled?
A. learning
B. forwarding
C. blocking
D. listening
58. What are two roles of Domain Name Services (DNS)? (Choose Two)
A. builds a flat structure of DNS names for more efficient IP operations
B. encrypts network Traffic as it travels across a WAN by default
C. improves security by protecting IP addresses under Fully Qualified Domain Names (FQDNs)
D. enables applications to identify resources by name instead of IP address
E. allows a single host name to be shared across more than one IP address
59. How do TCP and UDP differ in the way they guarantee packet delivery?
A. TCP uses checksum, acknowledgement, and retransmissions, and UDP uses checksums only.
B. TCP uses retransmissions, acknowledgement and parity checks and UDP uses cyclic redundancy checks only.
C. TCP uses checksum, parity checks, and retransmissions, and UDP uses acknowledgements only.
D. TCP uses two-dimensional parity checks, checksums, and cyclic redundancy checks and UDP uses retransmissions only.
60. A device detects two stations transmitting frames at the same time. This condition occurs after the first 64 bytes of the frame is received interface counter increments?
A. collision
B. CRC
C. runt
D. late collision
61. Which technology is used to improve web traffic performance by proxy caching?
A. WSA
B. Firepower
C. ASA
D. FireSIGHT
62. Using direct sequence spread spectrum, which three 2.4-GHz channels are used to limit collisions?
A. 1,6.11
B. 1,5,10
C. 1,2,3
D. 5,6,7
63. Which type of attack can be mitigated by dynamic ARP inspection?
A. worm
B. malware
B. malware
D. man-in-the-middle
64. What are two benefits of controller-based networking compared to traditional networking?
A. controller-based increases network bandwidth usage, while traditional lightens the load on the network.
B. controller-based inflates software costs, while traditional decreases individual licensing costs
C. Controller-based reduces network configuration complexity, while traditional increases the potential for errors
D. Controller-based provides centralization of key IT functions. While traditional requires distributes management function
E. controller-based allows for fewer network failure, while traditional increases failure rates.
65. What software defined architecture plane assists network devices with making packet-forwarding decisions by providing Layer 2 reachability and Layer 3 routing information?
A. data plane
B. control plane
C. policy plane
D. management plane
66. Which WAN access technology is preferred for a small office / home office architecture?
A. broadband cable access
B. frame-relay packet switching
C. dedicated point-to-point leased line
D. Integrated Services Digital Network switching.
67. Which two WAN architecture options help a business scalability and reliability for the network? (Choose two)
A. asychronous routing
B. single-homed branches
C. dual-homed branches
D. static routing
E. dynamic routing
68. A wireless administrator has configured a WLAN; however, the clients need access to a less congested 5-GHz network for their voice quality. What action must be taken to meet the requirement?
A. enable AAA override
B. enable RX-SOP
C. enable DTIM
D. enable Band Select
69. What mechanism carries multicast traffic between remote sites and supports encryption?
A. ISATAP
B. GRE over iPsec
C. iPsec over ISATAP
D. GRE
70. An engineer must establish a trunk link between two switches. The neighboring switch is set to trunk or desirable mode. What action should be taken?
A. configure switchport nonegotiate
B. configure switchport mode dynamic desirable
C. configure switchport mode dynamic auto
D. configure switchport trunk dynamic desirable
71. Which type of information resides on a DHCP server?
A. a list of the available IP addresses in a pool
B. a list of public IP addresses and their corresponding names
C. usernames and passwords for the end users in a domain
D. a list of statically assigned MAC addresses
72. What is a function of Wireless LAN Controller?
A. register with a single access point that controls traffic between wired and wireless endpoints.
B. use SSIDs to distinguish between wireless clients.
C. send LWAPP packets to access points.
D. monitor activity on wireless and wired LANs
73. What role does a hypervisor provide for each virtual machine in server virtualization?
A. infrastructure-as-a-service.
B. Software-as-a-service
C. control and distribution of physical resources
D. services as a hardware controller.
74. Which technology must be implemented to configure network device monitoring with the highest security?
A. syslog
B. NetFlow
C. IP SLA
D. SNMPv3
75. What is the function of a server?
A. It transmits packets between hosts in the same broadcast domain.
B. It provides shared applications to end users.
C. It routes traffic between Layer 3 devices.
D. It Creates security zones between trusted and untrusted networks
76. Refer to the exhibit. Which type of configuration is represented in the output?
A. Ansible
B. JSON
C. Chef
D. Puppet
77. A port security violation has occurred on a switch port due to the maximum MAC address count being exceeded Which command must be configured to increment the security-violation count and forward an SNMP trap?
A. switchport port-security violation access
B. switchport port-security violation protect
C. switchport port-security violation restrict
D. switchport port-security violation shutdown
78. Which spanning-tree enhancement avoids the learning and listening states and immediately places ports in the forwarding state?
A. BPDUfilter
B. PortFast
C. Backbonefast
D. BPDUguard
79. What are two functions of a Layer 2 switch? (Choose two)
A. acts as a central point for association and authentication servers
B. selects the best route between networks on a WAN
C. moves packets within a VLAN
D. moves packets between different VLANs
E. makes forwarding decisions based on the MAC address of a packet
80. A manager asks a network engineer to advise which cloud service models are used so employees do not have to waste their time installing, managing, and updating software which is only used occasionally Which cloud service model does the engineer recommend?
A. infrastructure-as-a-service
B. platform-as-a-service
C. business process as service to support different types of service
D. software-as-a-service
81. What makes Cisco DNA Center different from traditional network management applications and their management of networks?
A. It only supports auto-discovery of network elements in a greenfield deployment.
B. It modular design allows someone to implement different versions to meet the specific needs of an organization.
C. It abstracts policy from the actual device configuration.
D. It does not support high availability of management functions when operating in cluster mode.
82. If a notice-level messaging is sent to a syslog server, which event has occurred?
A. A network device has restarted.
B. An ARP inspection has failed.
C. A routing instance has flapped.
D. A debug operation is running.
83. Refer to the exhibit. Which two statements about the interface that generated the output are true? (Choose two.)
A. Two secure MAC address are manually configured on the interface.
B. A syslog message is generated when the maximum number of secure MAC addresses is on the interface.
C. The interface is error-disabled.
D. The interface dynamically learned two secure MAC addresses.
E. An SNMP trap is generated when the maximum number of secure MAC addresses is reached on the interface.
84. Refer to the exhibit. Which two statements about the interface that generated the output are true? (Choose two.)
A. learned MAC addresses are deleted after five minutes of inactivity
B. the interface is error-diabled if packets arrive from a new unknown source address
C. it has dynamically learned two secure MAC addresses
D. it has dynamically learned three secure MAC addresses
E. the security violation counter increments if packets arrive from a new unknown source address
85. Which option best describes an API?
A. A contract that describes how various components communicate and exchange data with each other.
B. an architectural style (versus a protocol) for designing applications
C. a stateless client-server model
D. request a certain type of data by specifying the URL path that models the data
86. Which command verifies whether any IPv6 ACLs are configured on a router?
A. show ipv6 interface
B. show access-list
C. show ipv6 access-list
D. show ipv6 route
87. Which command can you enter to allow Telnet to be supported in addition to SSH?
A. transport input telnet ssh
B. transport input telnet
C. no transport input telnet
D. privilege level 15
88. What will happen if you configure the logging trap debug command on a router?
A. It causes the router to send messages with lower severity levels to the syslog server.
B. It causes the router to send all messages with the severity levels Warning, Error, Critical, and Emergency to the syslog server.
C. It causes the router to send all messages to the syslog server
D. It causes the router to stop sending all messages to the syslog server.
89. Which Cisco IOS command will indicate that interface Gigabit Ethernet 0/0 is configured via DHCP?
A. show ip interface GigabitEthernet 0/0 dhcp
B. show interface GigabitEthernet 0/0
C. show ip interface dhcp
D. show ip interface GigabitEthernet 0/0
E. show ip interface GigabitEthernet 0/0 brief
90. Which statement about the nature of NAT overload is true?
A. applies a one-to-many relationship to internal IP addresses
B. applies a one-to-one relationship to internal IP addresses
C. applies a many-to-many relationship to internal IP addresses
D. can be configured only on Gigabit interface
91. How does STP prevent forwarding loops at OSI Layer 2?
A. TTL
B. MAC address forwarding
C. Collision avoidance
D. Port blocking
92. Which three statements about MAC addresses are correct? (Choose three.)
A. To communicate with other devices on a network, a network device must have a unique MAC address.
B. The MAC address is also referred to as the IP address.
C. The MAC address of a device must be configured in the Cisco IOS CLI by a user with administrative privileges.
D. A MAC address contains two main components, the first of which identifies the manufacturer of the hardware and the second of which uniquely identifies the hardware.
E. An example of a MAC address is 0A:26:B8:D6:65:90.
93. Which two statements about the purpose of the OSI model are accurate? (Choose two.)
A. Defines the network functions that occur at each layer
B. Facilitates an understanding of how information travels throughout a network
C. Changes in one layer do not impact other layer
D. Ensures reliable data delivery through its layered approach
94. You have two paths for the 10.10.10.0 network – one that has a feasible distance of 3072 and the other of 6144. What do you need to do to load balance your EIGRP routes?
A. Change the maximum paths to 2
B. Change the configuration so they both have the same feasible distance
C. Change the variance for the path that has a feasible distance of 3072 to 2
D. Change the IP addresses so both paths have the same source IP address
95. Which of the following dynamic routing protocols are Distance Vector routing protocols?
A. IS-IS
B. EIGRP
C. OSPF
D. BGP
E. RIP
96. Refer to the exhibit. If R1 receives a packet destined to 172.16.1.1, to which IP address does it send the packet?
A. 192.168.14.4
B. 192.168.12.2
C. 192.168.13.3
D. 192.168.15.5
97. Refer to the exhibit. If RTR01 is configured as shown, which three addresses will be received by other routers that are running EIGRP on the network? (Choose three)
A. 192.168.2.0
B. 10.4.3.0
C. 10.0.0.0
D. 172.16.0.0
E. 172.16.4.0
98. Which two options are the best reasons to use an IPV4 private IP space?(choose two)
A. to enable intra-enterprise communication
B. to implement NAT
C. to connect applications
D. to conserve global address space
E. to manage routing overhead
99. Which command must you enter to guarantee that an HSRP router with higher priority becomes the HSRP primary router after it is reloaded?
A. standby 10 preempt
B. standby 10 version 1
C. standby 10 priority 150
D. standby 10 version 2
100. Which type does a port become when it receives the best BPDU on a bridge?
A. The designated port
B. The backup port
C. The alternate port
D. The root port
