Identify the wrongly matched pair

Options

A. Typhoid—Widal test
B. Plague-Viral disease
C. Malignant malaria-Plasmodium falciparum
D. Common cold—Rhinovirus

Answer

To solve the question of identifying the wrongly matched pair, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understand the Question**: The question asks us to identify the wrongly matched pair of disease and its causative agent or related test.

2. **Analyze Option A**:
- Disease: Typhoid
- Causative Agent: Salmonella typhi
- Confirmatory Test: Vidal test
- **Evaluation**: Typhoid is indeed caused by Salmonella typhi, and the Vidal test is used for confirmation. This is a correct match.

3. **Analyze Option B**:
- Disease: Plague
- Causative Agent: Yersinia pestis
- Statement: Plague is a viral disease.
- **Evaluation**: Plague is caused by the bacterium Yersinia pestis, not a virus. Therefore, this is an incorrect match.

4. **Analyze Option C**:
- Disease: Malignant malaria
- Causative Agent: Plasmodium falciparum
- **Evaluation**: Malignant malaria is indeed caused by Plasmodium falciparum. This is a correct match.

5. **Analyze Option D**:
- Disease: Common cold
- Causative Agent: Rhinovirus
- **Evaluation**: The common cold is caused by rhinoviruses. This is also a correct match.

6. **Conclusion**: After analyzing all the options, we find that Option B is the only one that contains a wrongly matched pair, as it incorrectly states that plague is a viral disease.

### Final Answer:
The wrongly matched pair is **Option B**: Plague - Viral disease (it should be bacterial).