Agaricus, alternaria and Aspergillus are genera of fungi which are included in three different classes. The respective order of these classes will be:

Options

A. Phycomycetes, Ascomycetes and Basidiomycetes
B. Basidiomycetes, Deuteromycetes and Ascomycetes
C. Ascomycetes, Basidiomycetes and Deuteromycetes
D. Basidiomycetes, Phycomcyetes and Ascomycetes.

Answer

To solve the question regarding the classification of the fungi genera Agaricus, Alternaria, and Aspergillus, we can follow these steps:

### Step 1: Identify the Class of Each Genus
1. **Agaricus**: This genus is known for including mushrooms and belongs to the class **Basidiomycetes**.
2. **Alternaria**: This genus is primarily known for its role as a plant pathogen and belongs to the class **Deuteromycetes** (also known as Fungi Imperfecti).
3. **Aspergillus**: This genus is known for its role in fermentation and as a source of antibiotics, and it belongs to the class **Ascomycetes**.

### Step 2: Arrange the Classes in Order
Now that we have identified the classes for each genus, we can arrange them in the order given in the question:
- **Agaricus** → Basidiomycetes
- **Alternaria** → Deuteromycetes
- **Aspergillus** → Ascomycetes

### Step 3: Write the Final Answer
The respective order of the classes for the genera Agaricus, Alternaria, and Aspergillus is:
- **Basidiomycetes**, **Deuteromycetes**, and **Ascomycetes**.

### Conclusion
Thus, the correct answer is:
- **Basidiomycetes, Deuteromycetes, and Ascomycetes**.

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