C# and OOP Concepts

Which of the following best describes C#?

• A markup language

• A low-level assembly language

• A modern, object-oriented, type-safe programming language

• A database query language

Which of the following statements about C# is true?

• C# runs directly on hardware

• C# is compiled into Intermediate Language (IL) and runs on the .NET runtime

• C# is interpreted line by line

• C# is not platform-independent

What is the difference between value types and reference types in C#?

• Value types store copies of data; reference types store memory addresses

• Reference types are faster than value types

• Value types are always strings

• There is no difference

Which of the following is a value type?

• class

• string

• int

• object

What keyword is used to define a constant value that cannot change?

• readonly

• final

• const

• static

Which collection type maintains key-value pairs and does not allow duplicate keys?

• ArrayList

• Dictionary

• Queue

• List

What is the main difference between a Hashtable and a Dictionary in C#?

• Hashtable is generic; Dictionary is not

• Hashtable allows any type of key and value (non-generic); Dictionary is generic and type-safe

• Dictionary allows duplicate keys

• Hashtable is faster than Dictionary

Which collection represents a FIFO (First-In-First-Out) structure?

• Stack

• Queue

• List

• LinkedList

In Object-Oriented Programming, which principle allows a class to inherit members from another class?

• Polymorphism

• Encapsulation

• Inheritance

• Abstraction

Which OOP principle is demonstrated when a method in a subclass overrides a method from the base class?

• Inheritance

• Encapsulation

• Polymorphism

• Composition