Coliphages are viruses parasitising

Options

A. Fungi
B. Alimentary canal
C. Escherichia coli
D. Yeast.

Answer

**Step-by-Step Solution:**

1. **Understanding Coliphages**: The term "coliphages" refers to a specific type of virus. The suffix "phage" indicates that these are viruses that infect other organisms. In this case, coliphages are known to infect bacteria.

2. **Identifying the Target Organism**: Coliphages specifically target coliform bacteria, which includes a group of bacteria commonly found in the environment, including Escherichia coli (E. coli).

3. **Defining Escherichia coli**: E. coli is a well-known bacterium that resides in the intestines of humans and animals. It is often used as a model organism in microbiology and is a common target for bacteriophages.

4. **Conclusion**: Based on the information that coliphages are viruses that infect E. coli, we can conclude that the correct answer to the question is that coliphages are viruses parasitizing Escherichia coli.

5. **Final Answer**: Therefore, the answer is option number 3: Escherichia coli.

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