Dengue fever is caused by

Options

A. bacteria
B. virus
C. protozoa
D. worms

Answer

**Step-by-Step Solution:**

1. **Identify the Disease**: The question asks about the causative agent of Dengue fever.

2. **Understand the Types of Pathogens**: There are three main types of pathogens that can cause diseases: bacteria, viruses, and protozoa.

3. **Eliminate Incorrect Options**:
- **Bacterial Diseases**: Dengue is not caused by bacteria. Examples of bacterial diseases include typhoid and pneumonia. Therefore, bacteria can be eliminated as a cause of Dengue.
- **Protozoal Diseases**: Dengue is also not caused by protozoa. Protozoal diseases include malaria, which is caused by the Plasmodium species. Thus, protozoa can also be eliminated as a cause of Dengue.

4. **Identify the Correct Pathogen**: Dengue fever is caused by a virus. Specifically, it is caused by the Dengue virus, which is classified under the family of viruses known as Arboviruses (arthropod-borne viruses).

5. **Conclusion**: The correct answer to the question "Dengue fever is caused by" is a virus.

**Final Answer**: Dengue fever is caused by a virus (specifically, the Dengue virus).

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