Ringworm is due to

Options

A. algae
B. virus
C. fungus
D. bacterium

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the causative agent of ringworm disease. We need to identify which type of pathogen is responsible for this condition.

2. **Identifying Pathogens**: Pathogens are organisms that cause diseases. The main types of pathogens include bacteria, viruses, fungi, and algae.

3. **Analyzing the Options**: The options provided are:
- Algae
- Virus
- Fungus
- Bacterium

4. **Eliminating Incorrect Options**:
- **Algae**: Algae are primarily photosynthetic organisms and are not known to cause diseases in humans. Therefore, this option can be eliminated.
- **Virus**: While viruses can cause various diseases, they are not responsible for ringworm. This option can also be eliminated.
- **Bacterium**: Bacteria are another type of pathogen, but they do not cause ringworm. Thus, this option is incorrect as well.

5. **Identifying the Correct Option**: The correct option is **Fungus**. Ringworm is caused by certain fungi, particularly those belonging to the genera Microsporum and Trichophyton. These fungi thrive in warm and moist environments, leading to the development of dry, scaly lesions on the skin, nails, or scalp, which are characteristic symptoms of ringworm.

6. **Conclusion**: Therefore, the causative agent of ringworm is a fungus.

**Final Answer**: Ringworm is due to **fungus**.

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