Claviceps purpurea grows as parasite

Options

A. In human gut
B. In sugarcane roots
C. One pine needles
D. On fruits of grasses.

Answer

### Step-by-Step Solution:

1. **Understanding Claviceps purpurea**:
- Claviceps purpurea is a type of fungus commonly known as the ergot fungus. It primarily affects flowering grasses, particularly rye and other cereals.

2. **Identifying the Growth Habitat**:
- This fungus acts as a parasite, meaning it derives its nutrients from living plants. It specifically targets the reproductive structures of these plants.

3. **Analyzing the Options**:
- **Option A: In human gut**: This is incorrect as Claviceps purpurea does not grow in the human gut.
- **Option B: In sugarcane roots**: This is also incorrect since Claviceps purpurea does not inhabit sugarcane roots.
- **Option C: On pine needles**: This is incorrect as well; Claviceps purpurea does not grow on pine needles.
- **Option D: On fruits of the grasses**: This is the correct option. Claviceps purpurea grows as a parasite on the flowering parts of grasses, including their fruits.

4. **Conclusion**:
- Based on the analysis, the correct answer is that Claviceps purpurea grows as a parasite on the fruits of grasses.

### Final Answer:
**Claviceps purpurea grows as a parasite on fruits of the grasses.**

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