In which of the following classes of fungi, sexual reproduction is absent ?

Options

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

Answer

To solve the question "In which of the following classes of fungi, sexual reproduction is absent?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Classes of Fungi**:
- Fungi are classified into several groups based on their reproductive methods. The main classes include:
- Ascomycetes
- Basidiomycetes
- Zygomycetes
- Deuteromycetes (also known as Fungi Imperfecti)

2. **Identify the Reproductive Methods**:
- **Ascomycetes**: This class is known for sexual reproduction through ascospores. Example: Penicillium.
- **Basidiomycetes**: This class also reproduces sexually through basidiospores. Example: Eustiligo.
- **Zygomycetes**: This class can reproduce sexually through zygospores. Example: Rhizopus.
- **Deuteromycetes (Fungi Imperfecti)**: This class is characterized by the absence of sexual reproduction. They reproduce asexually through conidia. Example: Alternaria and Trichoderma.

3. **Analyze the Options**:
- Given the options, we need to determine which class does not undergo sexual reproduction.
- From our understanding, Deuteromycetes is the only class that lacks sexual reproduction.

4. **Conclude the Answer**:
- Therefore, the answer to the question is **Deuteromycetes**.

### Final Answer:
**Deuteromycetes (Fungi Imperfecti)** is the class of fungi in which sexual reproduction is absent.

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