The class of fungi which produce exogenous sexual spores is

Options

A. Phycomycetes
B. Ascomycetes
C. Basidiomycetes
D. Deuteromycetes

Answer

To solve the question "The class of fungi which produce exogenous sexual spores is", we will analyze the options provided and understand the characteristics of each class of fungi mentioned.

### Step-by-Step Solution:

1. **Understanding Exogenous Spores**:
- Exogenous spores are those that are produced externally, meaning they develop outside the parent structure.

2. **Analyzing the Options**:
- **Ficomycetes**: This class primarily reproduces through zoospores, which are formed endogenously (inside a structure). Therefore, they do not produce exogenous sexual spores.
- **Ascomycetes**: In Ascomycetes, sexual reproduction occurs through the formation of ascospores, which are produced endogenously within a sac-like structure called an ascus. Hence, they do not produce exogenous sexual spores.
- **Deuteromycetes**: Also known as "imperfect fungi," this class does not reproduce sexually at all; it only reproduces asexually. Therefore, it cannot be the answer.
- **Basidiomycetes**: This class is known for producing basidiospores, which are formed exogenously on specialized structures called basidia. This means they produce sexual spores externally.

3. **Conclusion**:
- Since Basidiomycetes are the only class among the options that produces exogenous sexual spores, the correct answer is **Basidiomycetes**.

### Final Answer:
The class of fungi which produce exogenous sexual spores is **Basidiomycetes**.

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