Give the structure of an optically active alkyne `(A)` having the lowest molecular mass, which on hydrogenation with Lindlard's catalyst and Birch reduction gives the same lowest molecular mass optically active alkene.

Explanation

To solve the problem, we need to find an optically active alkyne (A) with the lowest molecular mass that, upon hydrogenation with Lindlar's catalyst and Birch reduction, yields the same optically active alkene. Here’s a step-by-step breakdown of the solution:

### Step 1: Identify the Structure of the Optically Active Alkyne (A)
We need an alkyne that has a chiral center, which will make it optically active. The simplest alkyne that can be considered is 3-methyl-1-butyne. Its structure can be represented as follows:

```
CH3
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