Typhoid fever in human beings is caused by

Options

A. Plasmodium vivax
B. Trichophyton
C. Salmonella typhi
D. Rhino viruses.

Explanation

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks about the causative agent of typhoid fever in humans.

2. **Identify the Options**: The options provided are:
- A) Plasmodium
- B) Trichophyton
- C) Salmonella typhi
- D) Rhinovirus

3. **Analyze Each Option**:
- **Plasmodium**: This is a genus of parasites that cause malaria, not typhoid fever.
- **Trichophyton**: This is a genus of fungi that causes skin infections, not typhoid fever.
- **Salmonella typhi**: This is a type of bacteria specifically known to cause typhoid fever.
- **Rhinovirus**: This is a virus responsible for the common cold, not typhoid fever.

4. **Determine the Correct Answer**: Based on the analysis, the only option that correctly identifies the causative agent of typhoid fever is **C) Salmonella typhi**.

5. **Conclusion**: Therefore, the correct answer to the question is **C) Salmonella typhi**.

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