Logic Gates question from JEE Main 2021 (26 Aug, Shift 2)

Answer: (d)

1. Gate 1: $N = \overline{A + B}$.
2. Gate 2: $P = \overline{A + N}$; gate 3: $Q = \overline{B + N}$.
3. Check rows: $(0,0)$: $N = 1, P = 0, Q = 0, Y = \overline{0 + 0} = 1$.
4. $(0,1)$: $N = 0, P = 1, Q = 0, Y = 0$; $(1,0)$: $N = 0, P = 0, Q = 1, Y = 0$; $(1,1)$: $N = 0, P = 0, Q = 0, Y = 1$.
5. $Y$ = 1, 0, 0, 1 (XNOR), so the answer is (d).