Deficiency of which of the following does not cause chlorosis?

Options

A. Mo
B. Cu
C. Fe
D. Zn

Answer

To solve the question "Deficiency of which of the following does not cause chlorosis?", we will analyze the role of each nutrient mentioned in the options regarding chlorophyll production and chlorosis.

### Step-by-Step Solution:

1. **Understanding Chlorosis**:
- Chlorosis is a condition in plants characterized by yellowing of leaves due to insufficient chlorophyll production. Chlorophyll is essential for photosynthesis and gives leaves their green color.

2. **Identifying Nutrients**:
- The question provides several nutrients: molybdenum, copper, iron, and zinc. We need to determine which of these does not lead to chlorosis when deficient.

3. **Analyzing Molybdenum**:
- Molybdenum is essential for nitrogen metabolism in plants. A deficiency can lead to chlorosis because it affects the plant's ability to utilize nitrogen effectively, which is crucial for chlorophyll synthesis.

4. **Analyzing Copper**:
- Copper is involved in various enzymatic processes in plants. While its deficiency can lead to stunted growth and other issues, it does not directly cause chlorosis. Therefore, copper is a strong candidate for our answer.

5. **Analyzing Iron**:
- Iron is a critical component of chlorophyll. A deficiency in iron directly leads to chlorosis, as it is necessary for the formation of chlorophyll molecules.

6. **Analyzing Zinc**:
- Zinc plays a role in various plant functions, including chlorophyll production. A deficiency in zinc can also lead to chlorosis, as it is involved in the synthesis of chlorophyll.

7. **Conclusion**:
- After analyzing the roles of each nutrient, we conclude that the deficiency of **copper** does not cause chlorosis, making it the correct answer to the question.

### Final Answer:
**Copper**