Puccinia is

Options

A. a fungus that produces antibiotic
B. a fungus of class Phycomycetes
C. fungus that causes rust disease
D. an imperfect fungus

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about "Puccinia" and provides four options related to its classification or characteristics.

2. **Analyzing the Options**:
- **Option 1**: A fungus that produces antibiotic.
- This is incorrect because the well-known antibiotic-producing fungus is Penicillium, not Puccinia.

- **Option 2**: A fungus of class 5-comycetes.
- This is also incorrect. Puccinia does not belong to the class of fungi known as Zygomycetes (which includes Rhizopus and Mucor).

- **Option 3**: Fungus that causes rust disease.
- This is correct. Puccinia is known for causing rust diseases in plants, which are significant agricultural pathogens.

- **Option 4**: An imperfect fungus.
- This is incorrect as Puccinia is not classified as an imperfect fungus (Deuteromycetes).

3. **Conclusion**: After analyzing all options, the only correct answer is that Puccinia is a fungus that causes rust disease.

**Final Answer**: Puccinia is a fungus that causes rust disease.

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