Single stranded DNA was first reported by Fiers and Sinsheimer in

Options

A. (a) coliphage `phi xx 174`
B. (b) phage `phi beta`
C. (c) coliphage `phi 6`
D. (d) Rous Sarcoma virus

Answer

**Step-by-Step Solution:**

1. **Identify the Researchers and Year**: The question asks about the first report of single-stranded DNA by Fiers and Sinsheimer. It is important to note that this discovery was made in 1962.

2. **Understand the Context**: The researchers conducted their experiments on a specific type of virus. This virus is known as a bacteriophage, which is a virus that infects bacteria.

3. **Recognize the Specific Bacteriophage**: The specific bacteriophage studied by Fiers and Sinsheimer is referred to as coliphage. The designation "coliphage" indicates that this virus specifically infects E. coli, a common bacterium.

4. **Identify the Coliphage Type**: The exact type of coliphage reported by Fiers and Sinsheimer is coliphage phi 174. This is crucial as it distinguishes it from other types of bacteriophages.

5. **Conclude the Answer**: Based on the information gathered, the answer to the question is that single-stranded DNA was first reported by Fiers and Sinsheimer in the bacteriophage known as coliphage phi 174.

**Final Answer**: Coliphage phi 174.

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