Major function CK is to

Options

A. Mobilise nutrients and prevent senescence
B. Mobilise nutrients
C. Prevent senescene
D. Produce IAA.

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks about the major function of cytokinin (CK), which is a plant hormone.

2. **Understand Cytokinin's Role**: Cytokinins are known to play a crucial role in plant growth and development. They are primarily involved in promoting cell division.

3. **Functions of Cytokinin**:
- **Nutrient Mobilization**: Cytokinins help in mobilizing nutrients within the plant, especially at the site of application.
- **Prevention of Senescence**: They also play a significant role in delaying leaf senescence (aging), which helps in maintaining the health and vitality of the plant.

4. **Analyze the Options**:
- **Option 1**: Mobilizes nutrients and prevents senescence.
- **Option 2**: Mobilizes nutrients.
- **Option 3**: Prevents senescence.
- **Option 4**: Produces IAA (Indole-3-acetic acid).

5. **Determine the Correct Answer**: Since the major functions of cytokinin include both mobilizing nutrients and preventing senescence, the most accurate choice is **Option 1**.

6. **Conclusion**: The major function of cytokinin is to mobilize nutrients and prevent senescence.

### Final Answer:
The major function of cytokinin (CK) is to mobilize nutrients and prevent senescence (Option 1).

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