Cell mitosis is induced by

Options

A. Colchicine
B. Gibberellic acid
C. Nitrosoguanidine
D. Kinetin.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks what induces cell mitosis. Mitosis is the process of cell division, which is crucial for growth and development in organisms.

2. **Identifying the Options:** The options provided are:
- a) Colchicine
- b) Gibberellic acid
- c) Nitrosoguanidine
- d) Kinetin

3. **Analyzing Each Option:**
- **Colchicine:** This compound is known to inhibit mitosis by disrupting the spindle formation, so it does not induce mitosis.
- **Gibberellic Acid:** This is a plant hormone that promotes growth but is not primarily known for inducing mitosis.
- **Nitrosoguanidine:** This is a chemical mutagen and does not directly induce mitosis.
- **Kinetin:** This is a type of cytokinin, which is a class of plant hormones known to promote cell division and induce mitosis.

4. **Conclusion:** Based on the analysis, Kinetin (option d) is the correct answer as it is a plant hormone that induces cell mitosis by promoting cell division.

5. **Final Answer:** The correct option is **d) Kinetin**.

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