Inhibitory substances in dormant seeds cannot be removed by subjecting seeds to:

Options

A. Gibberellic acid
B. Nitrate
C. Ascorbic acid
D. Chilling conditions

Answer

To solve the question regarding which inhibitory substances in dormant seeds cannot be removed by subjecting seeds to certain conditions, we can analyze each option provided.

### Step-by-Step Solution:

1. **Understanding Seed Dormancy**:
- Dormant seeds have inhibitory substances that prevent germination. These substances must be removed or neutralized for the seed to germinate.

2. **Analyzing the Options**:
- **Option A: Gibberellic Acid**:
- Gibberellic acid is a plant hormone that promotes seed germination. It helps in breaking dormancy by stimulating the growth processes. Therefore, it can remove inhibitory substances.

- **Option B: Nitrate**:
- Nitrates are known to promote germination in many seeds. They can help in breaking dormancy by providing necessary nutrients and signals for growth. Thus, they can also remove inhibitory substances.

- **Option C: Ascorbic Acid**:
- Ascorbic acid (Vitamin C) is not known to promote germination; in fact, it can promote seed dormancy. It does not help in breaking down inhibitory substances in dormant seeds.

- **Option D: Chilling Conditions**:
- Chilling conditions (cold stratification) are often used to break dormancy in seeds that require a period of cold exposure. This method is effective in removing inhibitory substances.

3. **Conclusion**:
- Based on the analysis, the substance that cannot remove inhibitory substances in dormant seeds is **Ascorbic Acid** (Option C).

### Final Answer:
The correct answer is **C. Ascorbic Acid**.