Select the pair of diseases that are caused by contaminated water.

Options

A. Cholera and typhoid
B. Diarrhoea and diptheria
C. Pneumonia and dysentery
D. Malaria and influenza

Explanation

To determine the pair of diseases caused by contaminated water, we can analyze the options provided and identify which diseases are linked to water contamination.

### Step-by-Step Solution:

1. **Identify the Diseases in Each Option**:
- Option 1: Cholera and Typhoid
- Option 2: Diarrhea and Diphtheria
- Option 3: Pneumonia and Dysentery
- Option 4: Malaria and Influenza

2. **Analyze Each Disease**:
- **Cholera**: Caused by the bacterium Vibrio cholerae, which is transmitted through contaminated water.
- **Typhoid**: Caused by the bacterium Salmonella typhi, also spread through contaminated water.
- **Diarrhea**: Often caused by various pathogens that can be present in contaminated water, but it is a broad term and can be caused by many factors.
- **Diphtheria**: Caused by the bacterium Corynebacterium diphtheriae, primarily spread through respiratory droplets, not water.
- **Pneumonia**: Generally caused by bacteria or viruses that are transmitted through the air, not water.
- **Dysentery**: Often caused by bacteria or parasites, and can be linked to contaminated water.
- **Malaria**: Caused by the Plasmodium parasite, transmitted by mosquitoes, not water.
- **Influenza**: A viral infection spread through respiratory droplets, not water.

3. **Determine the Correct Pair**:
- From the analysis, **Cholera and Typhoid** are both diseases that are specifically caused by contaminated water.
- While Diarrhea can be linked to contaminated water, Diphtheria is not. Pneumonia is airborne, and Malaria and Influenza are also not caused by water contamination.

4. **Conclusion**: The correct pair of diseases caused by contaminated water is **Cholera and Typhoid**.

### Final Answer:
**Cholera and Typhoid**

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