Hormone used in suspension culture is:

Options

A. 2,4-D
B. NAA
C. BAP
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the specific hormone that is used in suspension culture in plant tissue culture.

2. **Identifying the Options**: The options provided are:
- 2,4-D (2,4-Dichlorophenoxyacetic acid)
- NAA (1-naphthalene acetic acid)
- BAP (Benzylaminopurine)
- None of these

3. **Analyzing Each Option**:
- **2,4-D**: This is primarily used as a herbicide and is known for its role in promoting cell division and differentiation in tissue culture, but it is not specifically the hormone used in suspension culture.
- **NAA**: This is a synthetic plant hormone that acts as a rooting agent and is widely used in plant tissue culture techniques, including suspension culture.
- **BAP**: This is a cytokinin that promotes cell division and is used in various plant tissue culture applications but is not specifically known for suspension culture.
- **None of these**: This option implies that none of the provided hormones are used in suspension culture, which is incorrect based on the analysis.

4. **Conclusion**: Based on the analysis, the hormone specifically used in suspension culture is **NAA (1-naphthalene acetic acid)**.

5. **Final Answer**: The correct answer is **NAA**.

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