Which is not correctly matched

Options

A. dengue fever-Arbovirus
B. plague-Yersinia pestis
C. sleeping sickness -Trypanosoma
D. syphilis-Treponema pallidum

Answer

To determine which option is not correctly matched, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Option 1: Dengue Fever and Arbovirus**
- Dengue fever is indeed caused by a virus, but it is specifically caused by the Dengue virus, which belongs to the Flavivirus family. Arbovirus refers to a broader category of viruses transmitted by arthropods (like mosquitoes), which includes many viruses other than Dengue. Therefore, this option is not correctly matched.

2. **Option 2: Plague and Yersinia pestis**
- Plague is caused by the bacterium Yersinia pestis. This is a well-established fact in microbiology and infectious disease studies. Therefore, this option is correctly matched.

3. **Option 3: Sleeping Sickness and Trypanosoma**
- Sleeping sickness is caused by the protozoan parasite Trypanosoma, specifically Trypanosoma brucei. This is also a well-known fact. Thus, this option is correctly matched.

4. **Option 4: Syphilis and Treponema pallidum**
- Syphilis is caused by the bacterium Treponema pallidum. This is another established fact in the study of sexually transmitted infections. Therefore, this option is correctly matched.

### Conclusion:
The only option that is not correctly matched is **Option 1: Dengue Fever and Arbovirus**. The correct causative agent for Dengue fever is the Dengue virus, not just the broader category of arboviruses.

### Final Answer:
**Option 1: Dengue Fever and Arbovirus is not correctly matched.**

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