Bud dormancy is induced by

Options

A. I A A
B. GA
C. ABA
D. ethylene

Explanation

### Step-by-Step Solution

1. **Understanding Bud Dormancy**:
- Bud dormancy is a physiological state where the growth and activity of buds are temporarily suspended. This state can be reactivated under favorable conditions.

2. **Identifying Causes of Bud Dormancy**:
- Bud dormancy often occurs in response to environmental factors such as seasonal changes, extreme heat, drought, or cold temperatures.

3. **Analyzing the Hormones**:
- The question provides four options regarding which hormone induces bud dormancy:
- **A. Indole-3-acetic acid**: This is a natural auxin that promotes growth and development, particularly in seedless fruits, but does not induce dormancy.
- **B. Gibberellic acid**: This hormone is known for breaking seed dormancy and promoting germination, not inducing dormancy.
- **C. Abscisic acid**: This hormone is often referred to as the stress hormone. Its concentration increases during stress conditions, leading to the induction of bud dormancy.
- **D. Ethylene**: This gaseous hormone is involved in processes like senescence and abscission, and it can break dormancy but does not induce it.

4. **Conclusion**:
- Based on the analysis, abscisic acid (option C) is the hormone that induces bud dormancy, particularly in response to stress conditions.

### Final Answer:
- Bud dormancy is induced by **C. Abscisic acid**.

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