Option B
Explanation :
Looking at the automata, the only way to get 1 as the output is when the transaction is from s3 state to s1 state for the input symbol 1
Now analyze how to reach s3, it's via the input 11 followed by 0
i.e. We r looking for the pattern 1101
Only option b has this pattern twice
So only option b will give 1 as output twice