Zinc has a role in :

Options

A. `NO_(3)^(-)` reduction
B. Carbonic anhydrase activity
C. sugar translocation
D. Amylase activity

Answer

### Step-by-Step Solution:

1. **Understanding the Role of Zinc in Plants**:
- Zinc is classified as a micronutrient, meaning it is required by plants in smaller quantities compared to macronutrients.

2. **Identifying Functions of Zinc**:
- Zinc is known to activate various enzymes in plants. It plays a crucial role in the activity of carbonic anhydrase, which is important for the conversion of carbon dioxide and water to bicarbonate and protons.

3. **Examining Specific Functions**:
- The transcript mentions that zinc is involved in nitrate reduction, sugar translocation, amylase activity, and carbonic anhydrase activity. However, it specifically states that zinc is not responsible for nitrate reduction, sugar translocation, or amylase activity.

4. **Highlighting the Key Role**:
- The key role of zinc highlighted in the transcript is its involvement in carbonic anhydrase activity and the synthesis of auxin, a plant hormone that regulates various growth processes.

5. **Conclusion**:
- From the information provided, we can conclude that zinc primarily plays a role in carbonic anhydrase activity and is essential for the synthesis of auxin.

### Final Answer:
Zinc has a role in carbonic anhydrase activity and the synthesis of auxin in plants.

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