Which one prevents premature fall of fruit ?

Options

A. `GA_(3)`
B. NAA
C. Ethylene
D. Zeatin

Answer

To answer the question "Which one prevents premature fall of fruit?" we need to analyze the options provided: GA3, NAA, Ethylene, and Zeatin.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for a substance that prevents the premature fall of fruit. This involves understanding the role of various plant hormones.

2. **Analyzing the Options**:
- **GA3 (Gibberellic Acid)**: This hormone is known for promoting growth and elongation in plants. It does not specifically prevent the fall of fruit.
- **NAA (Naphthalene Acetic Acid)**: This is a synthetic plant hormone from the auxin family. It is known to prevent the premature fall of fruits and is often used in horticulture for this purpose.
- **Ethylene**: This is a natural plant hormone that promotes fruit ripening and can actually lead to the dropping of fruits rather than preventing it.
- **Zeatin**: This is a cytokinin that promotes cell division and growth but does not have a direct role in preventing fruit drop.

3. **Identifying the Correct Answer**: Based on the analysis, NAA (Naphthalene Acetic Acid) is the hormone that prevents premature fall of fruit.

4. **Conclusion**: The correct answer to the question is **NAA**.

### Final Answer:
**NAA (Naphthalene Acetic Acid)** prevents the premature fall of fruit.

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