IGDTUW 2026 — Computer PYQ

The correct option is (b) $0$.

Detailed Solution & Explanation

The XOR (Exclusive OR) gate is a digital logic gate that implements an exclusive disjunction. The fundamental rule for an XOR operation is that it outputs a $1$ (HIGH) if and only if the inputs are different. If the inputs are the same, the output is $0$ (LOW).

Boolean Expression:

For two inputs $A$ and $B$, the output $Y$ of an XOR gate is represented mathematically as:

$$Y=A\oplus B=A\bar{B}+\bar{A}B$$

Truth Table of an XOR Gate:

The truth table clearly defines all possible input-output conditions for a 2-input XOR operation:

Calculation for the Given Question:

Substituting $A=1$ and $B=1$ into the algebraic expression:

$$Y=1\oplus 1$$

$$Y=(1\cdot \bar{1})+(\bar{1}\cdot 1)$$

$$Y=(1\cdot 0)+(0\cdot 1)$$

$$Y=0+0=0$$

Since both inputs are identical ($1$ and $1$), the XOR logic rules specify that they cancel each other out, resulting in an output of $0$.