Comma-shaped bacteria are

Options

A. Vibrio
B. Spirillum
C. Spirochaete
D. Coccus.

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks to identify which type of bacteria is comma-shaped from the given options.

2. **Review the Options**: The options provided are:
- Option 1: Vibrio
- Option 2: Pyrrolum
- Option 3: Pyrocate
- Option 4: Caucus

3. **Analyze Each Option**:
- **Option 1: Vibrio**: This type of bacteria is known for its comma-like shape, characterized by a single curve. Examples include *Vibrio cholerae* and *Vibrio vulnificus*.
- **Option 2: Pyrrolum**: This genus of bacteria is spiral-shaped, not comma-shaped.
- **Option 3: Pyrocate**: This type of bacteria is described as spirally twisted, which means it does not have a comma shape.
- **Option 4: Caucus**: This refers to round-shaped bacteria, which is also not comma-shaped.

4. **Identify the Correct Answer**: Based on the analysis, the only option that describes a comma-shaped bacterium is **Option 1: Vibrio**.

5. **Conclusion**: Therefore, the correct answer to the question "Comma-shaped bacteria are" is **Vibrio**.

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