Gaseous growth hormone is

Options

A. IAA
B. GA
C. Kinetin
D. Ethylene.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the identification of a gaseous growth hormone among the provided options.

2. **Reviewing the Options**: The options given are:
- IAA (Indole Acetic Acid)
- GA (Gibberellic Acid)
- Kinetin
- Ethylene

3. **Identifying Gaseous Hormones**: Among the options, we need to identify which one is known to be a gaseous hormone.

4. **Analyzing Each Option**:
- **IAA (Indole Acetic Acid)**: This is a plant hormone that is not gaseous; it is a type of auxin.
- **GA (Gibberellic Acid)**: This is also a non-gaseous hormone, primarily involved in promoting growth and elongation.
- **Kinetin**: This is a type of cytokinin and is not gaseous.
- **Ethylene**: This is known to be a gaseous plant hormone and is often referred to as the ripening hormone.

5. **Confirming Ethylene's Role**: Ethylene is synthesized in ripening fruits, flowers, and leaves. It plays a crucial role in various plant processes, including:
- Inducing fruit ripening
- Softening of fruit texture
- Changing color during ripening
- Inducing leaf abscission and senescence
- Promoting seed germination

6. **Final Answer**: Based on the analysis, the gaseous growth hormone is **Ethylene**.

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