ABA acts antagonistic to

Explanation

**Step-by-Step Solution:**

1. **Understanding ABA**: Abscisic Acid (ABA) is a plant hormone that plays a crucial role in plant stress responses. It is often referred to as a "stress hormone" because it helps plants cope with stressful conditions such as drought.

2. **Function of ABA**: One of the primary functions of ABA is to induce seed dormancy. This means that ABA prevents seeds from germinating under unfavorable conditions, allowing them to remain inactive until conditions improve.

3. **Identifying the Antagonistic Hormone**: The question asks for the hormone that acts antagonistically to ABA. Antagonistic means that it has an opposing effect.

4. **Role of Gibberellic Acid**: Gibberellic Acid (GA) is another plant hormone that has the opposite effect of ABA. While ABA induces seed dormancy, gibberellic acid promotes seed germination by breaking down the dormancy that ABA induces.

5. **Conclusion**: Therefore, the hormone that acts antagonistically to ABA is Gibberellic Acid (GA), as it counteracts the effects of ABA by promoting germination and breaking seed dormancy.

**Final Answer**: ABA acts antagonistically to Gibberellic Acid (GA).

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