Credit for construction of first recombinant DNA may be given to

Options

A. Charles Darwin and Alfred Wallace
B. Stanley Cohen and Herbert Boyer
C. Meselson and Stahl
D. Esther and Joshua Lederberg

Answer

To answer the question regarding who is credited with the construction of the first recombinant DNA, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Recombinant DNA**:
- Recombinant DNA is formed by combining DNA from two different sources. This technology allows for the insertion of a gene of interest into a plasmid (a small circular DNA molecule) which can then be introduced into a host organism.

2. **Identifying Key Contributors**:
- The question lists several scientists: Charles Darwin, Alfred Wallace, Stanley Cohen, Herbert Boyer, Meselson, Stahl, Esther, and Joshua Lederberg. We need to determine who among them is associated with recombinant DNA technology.

3. **Analyzing Each Scientist's Contribution**:
- **Charles Darwin and Alfred Wallace**: Known for their work on the theory of evolution, not recombinant DNA.
- **Stanley Cohen and Herbert Boyer**: They are credited with the development of recombinant DNA technology in the 1970s. They successfully combined DNA from different organisms, which is the foundation of recombinant DNA.
- **Meselson and Stahl**: Known for their experiments that demonstrated the semi-conservative nature of DNA replication, not directly related to recombinant DNA.
- **Esther and Joshua Lederberg**: They contributed to genetics and microbiology but are not primarily known for recombinant DNA technology.

4. **Conclusion**:
- The correct answer is Stanley Cohen and Herbert Boyer, as they are recognized for constructing the first recombinant DNA.

### Final Answer:
The credit for the construction of the first recombinant DNA may be given to **Stanley Cohen and Herbert Boyer**.

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