MCQs on Combinational Circuits

Which of the following is a combinational circuit?

• Flip-Flop

• Counter

• Multiplexer

• Register

A decoder with ‘n’ input lines can have a maximum of how many output lines?

• 2ⁿ

• n²

• n

• 2n

Which combinational circuit converts binary information from 'n' input lines to a maximum of 2ⁿ unique output lines?

• Encoder

• Decoder

• Multiplexer

• Demultiplexer

What is the primary function of a multiplexer?

• Convert parallel data to serial

• Select one output from many inputs

• Select one input from many outputs

• Convert serial data to parallel

A full adder has how many inputs and outputs?

• 2 inputs, 1 output

• 3 inputs, 2 outputs

• 3 inputs, 1 output

• 2 inputs, 2 outputs

Which of the following circuits is used to perform binary addition?

• Decoder

• Flip-Flop

• Adder

• Multiplexer

A 4-to-1 multiplexer has how many select lines?

• 1

• 2

• 4

• 8

What is the minimum number of full adders required to add two 4-bit binary numbers?

• 1

• 2

• 3

• 4

Which combinational circuit performs the reverse operation of a decoder?

• Multiplexer

• Demultiplexer

• Encoder

• Adder

The main difference between a decoder and a demultiplexer is:

• Decoder has select lines, demux does not

• Decoder is sequential, demux is combinational

• Decoder has no data input, demux has one data input

• Decoder can store data, demux cannot