Cytokinins are mostly produced in

Options

A. Shoot apex
B. Root apex
C. Young leaves
D. Lateral buds.

Answer

### Step-by-Step Solution:

1. **Understanding Cytokinins**: Cytokinins are a class of plant hormones that play a crucial role in promoting cell division and delaying the aging process (senescence) of leaves.

2. **Identifying Production Sites**: The question asks where cytokinins are mostly produced. The options given are:
- Shoot apex
- Root apex
- Young leaves
- Lateral buds

3. **Analyzing Each Option**:
- **Shoot Apex**: While cytokinins can be found here, they are not primarily produced in this region.
- **Root Apex**: This is the primary site of cytokinin production. The root apex synthesizes cytokinins, which are then transported to other parts of the plant.
- **Young Leaves**: Young leaves are involved in growth and development, but they do not primarily produce cytokinins.
- **Lateral Buds**: Similar to young leaves, lateral buds do not primarily produce cytokinins.

4. **Conclusion**: Based on the analysis, the correct answer is that cytokinins are mostly produced in the **root apex**.

### Final Answer:
Cytokinins are mostly produced in the **root apex**.

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