……… is a bacteriophage that infects E.coli.

Options

A. Alpha 60
B. T2
C. TZ
D. Beta 60

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of a bacteriophage that specifically infects E. coli.

2. **Defining Bacteriophage**: A bacteriophage, or phage, is a type of virus that infects bacteria. It attaches to the bacterial cell, injects its genetic material, and takes over the bacterial machinery to replicate itself.

3. **Identifying the Options**: The options provided are alpha 60, T2, TZ, and beta 60.

4. **Researching Bacteriophages**: Among the options, T2 is known as an enterobacteria phage, which means it is capable of infecting Enterobacteriaceae, a family of bacteria that includes E. coli.

5. **Selecting the Correct Answer**: Based on the information that T2 is a bacteriophage that infects E. coli, the correct answer to the question is **T2**.

**Final Answer**: T2 is a bacteriophage that infects E. coli.

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