A hormone delaying senescence is :

Options

A. Auxin
B. Cytokinin
C. Ethylene
D. Gibberellin

Answer

**Step-by-Step Solution:**

1. **Understanding Senescence**: Senescence refers to the process of aging in plants, which leads to the gradual deterioration of plant tissues and ultimately death.

2. **Identifying Plant Hormones**: Several hormones are involved in plant growth and development, including Auxins, Cytokinins, Ethylene, and Gibberellins. Each of these hormones has specific functions.

3. **Analyzing the Options**:
- **Auxin**: Primarily involved in stem elongation and does not delay senescence.
- **Cytokinin**: This hormone promotes cell division and is known to delay senescence by maintaining the health of leaves and other plant tissues.
- **Ethylene**: This hormone is associated with fruit ripening and does not delay senescence; rather, it can promote aging in some contexts.
- **Gibberellin**: This hormone is mainly involved in seed germination and growth, not in delaying senescence.

4. **Conclusion**: Among the options provided, Cytokinin is the hormone that delays senescence by promoting cell division and maintaining leaf vitality.

5. **Final Answer**: The hormone that delays senescence is **Cytokinin**.

---