ABA acts antagonistic to

Options

A. ethylene
B. cytokinin
C. gibberellic acid
D. IAA

Explanation

**Step-by-Step Solution:**

1. **Identify the Hormone in Question**: The question asks about ABA, which stands for abscisic acid. It is essential to recognize that ABA is a plant hormone.

2. **Understand the Term "Antagonistic"**: The term "antagonistic" means that one substance works against or opposes the action of another. In the context of plant hormones, this means that ABA will have effects that counteract those of another hormone.

3. **List the Given Options**: The options provided in the question are:
- Ethylene
- Cytokinin
- Gibberellic acid
- IAA (Indole-3-acetic acid)

4. **Analyze the Functions of ABA**:
- ABA inhibits growth.
- ABA promotes seed dormancy.
- ABA promotes leaf senescence (aging).

5. **Analyze the Functions of Gibberellic Acid**:
- Gibberellic acid promotes growth.
- Gibberellic acid overcomes seed dormancy.
- Gibberellic acid prevents leaf senescence.

6. **Determine the Antagonistic Relationship**: Based on the functions analyzed, ABA and gibberellic acid have opposing effects:
- ABA inhibits growth while gibberellic acid promotes it.
- ABA promotes dormancy while gibberellic acid overcomes it.
- ABA promotes leaf senescence while gibberellic acid prevents it.

7. **Conclude the Answer**: Since ABA acts antagonistically to gibberellic acid, the final answer to the question is that ABA acts antagonistic to gibberellic acid.

**Final Answer**: ABA acts antagonistic to gibberellic acid.

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