Little leaf disease is caused by

Options

A. Copper
B. Zinc
C. Manganese
D. Cobalt

Answer

### Step-by-Step Solution:

1. **Understanding Little Leaf Disease**:
- Little leaf disease is a condition that affects plants, leading to the development of smaller leaves than normal.

2. **Identifying the Cause**:
- Various mineral deficiencies can lead to different plant diseases. In this case, we need to identify which mineral deficiency is responsible for little leaf disease.

3. **Analyzing the Options**:
- The options provided are copper, zinc, manganese, and cobalt. We need to determine which of these minerals is linked to little leaf disease.

4. **Researching Mineral Deficiencies**:
- It is known that different minerals play specific roles in plant health. For example, zinc is essential for various enzymatic functions and growth regulation in plants.

5. **Conclusion**:
- Based on the information available, little leaf disease is specifically caused by the deficiency of zinc.

6. **Final Answer**:
- Therefore, the correct answer is **zinc**.