Expand. LH

Explanation

### Step-by-Step Solution:

1. **Identify the abbreviation**: The abbreviation given in the question is "LH".

2. **Recall the full form**: The full form of "LH" is "Luteinizing Hormone".

3. **Understand its function**: Luteinizing Hormone plays a crucial role in the reproductive system. In females, it is involved in regulating the menstrual cycle and triggering ovulation, which is the release of an egg from the ovary.

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