The process of senescence in plants can be reversed by applying

Options

A. ethylene
B. auxins
C. ABA
D. cytokinins

Answer

To answer the question regarding which plant growth regulator can reverse the process of senescence in plants, we will analyze the functions of the mentioned hormones: ethylene, auxins, abscisic acid (ABA), and cytokinins.

### Step-by-Step Solution:

1. **Understanding Senescence**:
- Senescence is the natural aging process in plants, which leads to the gradual deterioration of plant tissues and organs.

2. **Analyzing Ethylene**:
- Ethylene is a gaseous plant hormone that promotes ripening of fruits and increases respiration rates. It is primarily involved in processes that lead to senescence rather than reversing it. Therefore, it does not inhibit senescence.

3. **Analyzing Auxins**:
- Auxins are responsible for various growth processes, including apical dominance and xylem differentiation. While they play a role in growth, they do not specifically reverse senescence.

4. **Analyzing Abscisic Acid (ABA)**:
- ABA is known as the stress hormone and is responsible for processes such as stomatal closure and dormancy. It generally promotes senescence and stress responses, rather than reversing it.

5. **Analyzing Cytokinins**:
- Cytokinins are hormones that promote cell division and are known to delay leaf senescence. They help in nutrient mobilization and can counteract the aging process in plants.

6. **Conclusion**:
- Based on the functions of these hormones, cytokinins are the most effective in reversing or inhibiting the process of senescence in plants. Therefore, the correct answer is **cytokinins**.

### Final Answer:
The process of senescence in plants can be reversed by applying **cytokinins**.

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