The imperfect fungi which are decomposers of litter and help in mineral cycling belong to:

Options

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

Answer

### Step-by-Step Solution:

1. **Understanding Imperfect Fungi**:
- Imperfect fungi are those fungi that do not have a known sexual reproductive stage. This means that their sexual reproduction is either absent or not observed.

2. **Classification of Fungi**:
- Fungi are classified into various groups based on their reproductive methods. The imperfect fungi primarily fall under the class known as Deuteromycetes.

3. **Role of Deuteromycetes**:
- Deuteromycetes are known for their saprophytic (feeding on dead organic matter) or parasitic lifestyles. They play a crucial role in the ecosystem as decomposers.

4. **Decomposition and Mineral Cycling**:
- The fungi in this class help in the decomposition of organic litter, which is essential for mineral cycling. This process recycles nutrients back into the ecosystem.

5. **Examples of Decomposing Fungi**:
- An example of an imperfect fungus that acts as a decomposer is Coleotrichum. This fungus helps in breaking down organic matter, thus contributing to mineral cycling.

6. **Conclusion**:
- Therefore, the imperfect fungi that are decomposers of litter and assist in mineral cycling belong to the class Deuteromycetes.

### Final Answer:
The imperfect fungi which are decomposers of litter and help in mineral cycling belong to the class **Deuteromycetes**.

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