The fungus that may cause disease in human beings is

Options

A. Aspergillus
B. Ustilago
C. Mushroom
D. Puccinia

Answer

### Step-by-Step Solution:

1. **Identify the Options**: The question provides four options: Aspergillus, ostilego, Mushroom, and Puccinia.

2. **Analyze Aspergillus**: Aspergillus is a genus of fungi known to cause various diseases in humans, collectively referred to as Aspergillosis. This can range from mild infections to severe, life-threatening conditions.

3. **Examine Puccinia**: Puccinia is a large genus of fungi that are obligate parasites, primarily affecting plants. While they are significant in agriculture, they do not typically cause diseases in humans.

4. **Consider Ostilego and Mushroom**: The term "ostilego" is not commonly recognized in the context of human diseases caused by fungi. Similarly, the term "Mushroom" generally refers to the fruiting body of certain fungi, many of which are edible and do not cause diseases in humans.

5. **Conclusion**: Based on the analysis, the fungus that may cause disease in human beings is **Aspergillus**.

### Final Answer:
The fungus that may cause disease in human beings is **Aspergillus**.

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