Give the structure of an optically active alkene `(A)` having the lowest molecular mass, which on catalytic hydrogenation gives an optically inactive compound `(B)`.

Explanation

To solve the question, we need to identify an optically active alkene (A) with the lowest molecular mass that, upon catalytic hydrogenation, yields an optically inactive compound (B).

### Step-by-Step Solution:

1. **Understanding Optical Activity**:
An optically active compound must have a chiral center, meaning it has four different substituents attached to a carbon atom.

2. **Choosing the Alkene**:
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