Escherichia coli is

Options

A. Gut bacterium
B. Soil bacterium
C. Thermal bacterium
D. Both A and B

Answer

**Step-by-Step Text Solution:**

1. **Identify the Organism**: Escherichia coli, commonly referred to as E. coli, is a type of bacteria.

2. **Common Name**: The abbreviation "E. coli" is widely used to refer to this organism.

3. **Natural Habitat**: E. coli is primarily found in two main habitats:
- The intestines (gut) of humans and other animals.
- Soil, particularly in areas near plant roots.

4. **Classification**: E. coli is classified as a gram-negative bacterium. This classification is based on its cell wall structure, which does not retain the crystal violet stain used in the Gram staining procedure.

5. **Significance**: E. coli is significant in both ecological and medical contexts. It plays a role in the digestive system of humans and animals but can also be associated with foodborne illnesses.

**Final Statement**: Therefore, Escherichia coli (E. coli) is a gram-negative bacterium commonly found in the intestines of humans and animals, as well as in soil near plant roots.

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