Which of the following is an edible fungus ?

Options

A. Mucor
B. Morchella
C. Puccinia
D. Ustilago

Explanation

To determine which of the following is an edible fungus, we will analyze each option provided:

1. **Option A: Mucor**
- Mucor is a filamentous fungus that typically grows on decaying organic matter such as rotting fruits and vegetables. It is not considered edible due to its potential to cause food spoilage and its association with mold. Therefore, this option is incorrect.

2. **Option B: Morchella**
- Morchella, commonly known as morel mushrooms, belongs to the Ascomycota division of fungi. Morels are well-known for being edible and are highly sought after in culinary dishes. Therefore, this option is correct.

3. **Option C: Ustilago**
- Ustilago is a genus of fungi that includes species known to be pathogenic, particularly those that infect plants (like corn smut). These fungi are not considered edible and are associated with plant diseases. Therefore, this option is incorrect.

4. **Option D: Aspergillus**
- Aspergillus is a genus of fungi that includes many species, some of which are pathogenic and can cause diseases in humans and animals. While some species of Aspergillus are used in fermentation (like for making soy sauce), they are not typically classified as edible fungi in the same way as mushrooms. Therefore, this option is incorrect.

**Conclusion:**
The only edible fungus among the options provided is **Morchella (Option B)**.

---