Rabies is caused by a

Options

A. Bacterium
B. Worm
C. Virus
D. Fungus.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks what causes rabies. We need to identify the correct pathogen responsible for this disease.

2. **Analyzing the Options:**
The options provided are:
- A) Bacterium
- B) Worm
- C) Virus
- D) Fungus

3. **Evaluating Each Option:**
- **Option A: Bacterium**
- Rabies is not caused by bacteria. Bacterial diseases are different and examples include typhoid and tuberculosis. Therefore, this option is incorrect.

- **Option B: Worm**
- Worms, such as flatworms and roundworms, are typically parasitic and do not cause rabies. Thus, this option is also incorrect.

- **Option C: Virus**
- Rabies is indeed caused by a virus known as the rabies virus. This is the correct option.

- **Option D: Fungus**
- Fungi can affect both animals and plants, but they do not cause rabies. Therefore, this option is incorrect as well.

4. **Conclusion:**
After evaluating all options, the correct answer is that rabies is caused by a virus.

**Final Answer:**
Rabies is caused by a virus.

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