Cholera, Typhoid, Tetanus, Citrus canker are well known diseases caused by:

Answer

To answer the question regarding the causative organisms of Cholera, Typhoid, Tetanus, and Citrus canker, we can break it down step by step:

### Step 1: Identify the diseases
We start by listing the diseases mentioned in the question:
1. Cholera
2. Typhoid
3. Tetanus
4. Citrus canker

### Step 2: Identify the causative organisms
Next, we need to identify the causative organisms for each of these diseases:

- **Cholera**: The causative organism is **Vibrio cholerae**, which is a bacterium. Cholera is characterized by acute diarrhea.

- **Typhoid**: The causative organism is **Salmonella typhi**, which is also a bacterium. Typhoid spreads through contaminated food and water.

- **Tetanus**: The causative organism is **Clostridium tetani**, another bacterium. Tetanus is known for causing muscle spasms.

- **Citrus canker**: The causative organism is **Xanthomonas citri**, which is a bacterium that affects plants, causing wilting of leaves and premature fruit drop.

### Step 3: Conclusion
All the diseases listed are caused by bacteria. The specific bacteria responsible for each disease are:
- Cholera: **Vibrio cholerae**
- Typhoid: **Salmonella typhi**
- Tetanus: **Clostridium tetani**
- Citrus canker: **Xanthomonas citri**

### Final Answer
Cholera, Typhoid, Tetanus, and Citrus canker are well-known diseases caused by bacteria.

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