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

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the credit of the construction of the first recombinant DNA. This requires knowledge of key figures in biotechnology and genetic engineering.

2. **Analyzing the Options**:
- **Option A: Charles Darwin and Alfred Wallace**: These scientists are known for their work on evolution, not for contributions to genetic engineering or recombinant DNA technology. Therefore, this option is incorrect.

- **Option B: Stanley Cohen and Herbert Boyer**: These two scientists are credited with the first successful construction of recombinant DNA. They isolated an antibiotic resistance gene and ligated it to a plasmid, creating a recombinant molecule. This is a significant milestone in biotechnology, making this option correct.

- **Option C: Meselson and Stahl**: Their work focused on DNA replication and confirmed that DNA is the genetic material. They did not contribute to the development of recombinant DNA, so this option is also incorrect.

- **Option D: Joshua Lederberg and Edward Tatum**: They conducted experiments on bacterial genetics and demonstrated the concept of genetic recombination in bacteria, but they did not create recombinant DNA. Thus, this option is also incorrect.

3. **Conclusion**: After analyzing all the options, it is clear that the correct answer is **Option B: Stanley Cohen and Herbert Boyer**.

**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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