What is the necessary and sufficient condition for a molecule to be optically active ?

Explanation

To determine the necessary and sufficient condition for a molecule to be optically active, we can follow these steps:

### Step-by-Step Solution:

1. **Definition of Optical Activity**:
- Optical activity refers to the ability of a substance to rotate the plane of polarized light. For a molecule to exhibit optical activity, it must be able to interact with polarized light in a specific way.

2. **Chirality Requirement**:
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