Arber, Smith and Nathans are famous for discovery of

Options

A. Gene therapy
B. Restriction enzyme
C. Humulin
D. Second generation vacciness

Answer

**Step-by-Step Solution:**

1. **Identify the Scientists**: The question mentions three scientists: Arber, Smith, and Nathans.

2. **Research Their Contributions**: These scientists are known for their work in molecular biology, particularly in the study of enzymes that cut DNA.

3. **Focus on Restriction Enzymes**: In the late 1960s and early 1970s, they conducted experiments that led to the discovery of restriction enzymes.

4. **Understand Restriction Enzymes**: Restriction enzymes are proteins that recognize specific nucleotide sequences in DNA and make precise cuts at those locations.

5. **Conclude the Discovery**: Based on their research and findings, Arber, Smith, and Nathans are famous for the discovery of restriction enzymes.

**Final Answer**: Arber, Smith, and Nathans are famous for the discovery of restriction enzymes.

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