Which of the following digital logic circuits can be used to add more than 1 – bit simultaneously?a.Full – adderb.Serial adderc.Half – adderd.Ripple – carry adder

The correct answer is a. Full – adder.

Here's why:

a. Full – adder: A full adder is a digital circuit that performs addition. It takes three inputs: A, B, and a carry from the previous digit (Cin). It outputs the sum of the three inputs (S) and a carry output (Cout). This allows it to add more than 1-bit simultaneously, making it the correct answer.

b. Serial adder: A serial adder is a digital circuit that can add two binary numbers bit-by-bit, serially. It cannot add more than 1-bit simultaneously.

c. Half – adder: A half adder is a simpler version of the full adder. It can only add two 1-bit numbers and does not account for carry from a previous digit. Therefore, it cannot add more than 1-bit simultaneously.

d. Ripple – carry adder: A ripple-carry adder is a digital circuit that can add two binary numbers. It is made up of several full adders, with the carry output from one full adder connected to the carry input of the next. While it can add multi-bit numbers, it does so bit-by-bit, not simultaneously.