To determine when the output $Y=0$, we identify the logic operation represented by the given circuit.

Since the options correspond to all four combinations of two inputs $A$ and $B$, this is a standard 2-input logic-gate evaluation problem. The circuit corresponds to an OR gate followed by a NOT gate, i.e. a NOR gate.

So,

Now evaluate for all input combinations.

1. Truth table

2. Find when $Y=0$

From the table, $Y=0$ for:

• $A=0, B=1$
• $A=1, B=0$
• $A=1, B=1$

Thus among the given options, the combinations giving $Y=0$ are:

• A: $A=1, B=0$
• C: $A=1, B=1$
• D: $A=0, B=1$

3. Comparison with stored answer

The stored correct answer is C only, but from the logic evaluation, $Y=0$ is obtained for A, C, and D.

Hence the stored answer appears incomplete/incorrect if this is intended as a single-choice question.