In which of the following will you look for Escherichia coli

Options

A. Water
B. Soil
C. Milk
D. Human intestine.

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The organism in question is Escherichia coli, commonly known as E. coli.

2. **Understand the Characteristics**: E. coli is a gram-negative, rod-shaped bacterium that is facultatively anaerobic, meaning it can grow in both the presence and absence of oxygen.

3. **Determine Natural Habitat**: E. coli is primarily found in the intestines of animals, including humans. It plays a significant role in digestion and maintaining gut health.

4. **Analyze the Options**: The options provided are:
- Water
- Soil
- Milk
- Human intestine

5. **Evaluate Each Option**:
- **Water**: E. coli can be found in water, especially if contaminated, but it is not its primary habitat.
- **Soil**: While some bacteria can be found in soil, E. coli is not typically associated with this environment.
- **Milk**: E. coli can contaminate milk, but it is not a natural habitat for this bacterium.
- **Human Intestine**: This is the primary habitat for E. coli, where it is normally found and plays a beneficial role.

6. **Select the Correct Answer**: Based on the analysis, the best answer is the **human intestine**, as this is where E. coli is predominantly found.

**Final Answer**: Human intestine

---