The edible fungi are

Options

A. Rusts
B. Moulds
C. Mildews
D. Mushrooms.

Answer

### Step-by-Step Solution:

1. **Identify the Options**: The question provides four options: rust, molds, mildews, and mushrooms.

2. **Evaluate Rust**: Rust fungi are parasitic and primarily infect plants, causing diseases. They are not edible. Therefore, this option is incorrect.

3. **Evaluate Molds**: Molds are a broad category of fungi that grow in multicellular filaments called hyphae. While some molds can be used in food production (like certain cheeses), they are not generally classified as edible fungi in the same way mushrooms are. Thus, this option is also incorrect.

4. **Evaluate Mildews**: Mildews are a type of mold growth and do not refer to a specific edible fungus. They are generally associated with mold growth and are not considered edible. Hence, this option is incorrect.

5. **Evaluate Mushrooms**: Mushrooms belong to the genus Agaricus, which includes over 300 species. Some of these species are edible, while others can be poisonous. Since mushrooms are widely recognized as edible fungi, this option is correct.

6. **Conclusion**: The correct answer to the question "The edible fungi are" is **mushrooms**.

### Final Answer:
The edible fungi are **mushrooms**.

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