NIMCET 2011 — Computer PYQ

Explanation of columns (from right to left):

1. First column: $0+1=1$

2. Second column: $1+1=10\to$ write 0, carry 1

3. Third column: $0+1+(\text{carry }1)=10\to$ write 0, carry 1

4. Fourth column: $1+1+(\text{carry }1)=11\to$ write 1, carry 1

5. Fifth column: $1+0+(\text{carry }1)=10\to$ write 0, carry 1

6. Final carry: Bring down the remaining 1.

The final result is $101001$.

Correct Option: (a)