Escherichia coil is a bacterium which is common inhabitant of

Options

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

Answer

**Step-by-Step Solution:**

1. **Identify the Bacterium**: The question refers to Escherichia coli, commonly known as E. coli.

2. **Understand the Characteristics of E. coli**: E. coli is a gram-negative bacterium and is classified as facultative aerobic. This means it can survive in both the presence and absence of oxygen.

3. **Determine the Common Habitat**: The question asks for the common inhabitant of E. coli. Research and biological studies indicate that E. coli is predominantly found in the human intestine.

4. **Discuss the Role of E. coli in the Intestine**: E. coli strains that inhabit the human intestine are generally harmless and form part of the normal gut flora. They play a crucial role in the digestive system by producing vitamin K2 and preventing the colonization of pathogenic bacteria.

5. **Evaluate the Options**: The options provided are:
- Option 1: Human intestine
- Option 2: Soil
- Option 3: Milk
- Option 4: Water
Based on the information gathered, the correct answer is Option 1: Human intestine.

6. **Conclusion**: E. coli is a common inhabitant of the human intestine, where it exists in a symbiotic relationship with the host, contributing to health by producing essential vitamins.

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