Clostrdium botulinum is

Options

A. Obligate aerobe
B. Facultative aerobes
C. Facultative anaerobe
D. Obligate anaerobe.

Answer

### Step-by-Step Solution:

1. **Understanding the Terms**:
- First, we need to understand the terms related to oxygen requirements of organisms:
- **Obligate Aerobes**: Organisms that require oxygen for survival.
- **Facultative Aerobes**: Organisms that can survive with or without oxygen but prefer oxygen.
- **Facultative Anaerobes**: Organisms that can survive with or without oxygen but do not require it.
- **Obligate Anaerobes**: Organisms that cannot survive in the presence of oxygen.

2. **Identifying Clostridium botulinum**:
- Clostridium botulinum is a type of bacterium. It is important to note its characteristics:
- It is **Gram-positive**.
- It is **rod-shaped**.
- It is known for being a **spore-forming bacterium**.

3. **Determining Oxygen Requirement**:
- Clostridium botulinum is classified as an **obligate anaerobe**. This means it cannot survive in the presence of oxygen and requires an oxygen-free environment to grow.

4. **Choosing the Correct Option**:
- Based on the definitions and characteristics, the correct answer to the question "Clostridium botulinum is" is:
- **Obligate Anaerobe** (Option 4).

### Final Answer:
Clostridium botulinum is an **obligate anaerobe**.

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