All the following statements about Stanley Cohen and Herbert Boyer are correct but one is wrong. Which one is wrong

Options

A. They discovered recombinant DNA (r-DNA) technology which marked the birth of modern biotechnology
B. They first produced. Healthyl sheep clone, a Finn Dorst lamb, Dolly from the differentaited adult mammary cells.
C. They invented genetic engineering by combining a piece of foreign DNA containing a gene from a bacterium with a bacterial (E coli) plasmid using the enzyme restriction endonuclease
D. They isolated the antibiotic resistance gene by cutting out a piece of DNA from a plasmid which was responsible for conferring antibiotic resistance .

Answer

To determine which statement about Stanley Cohen and Herbert Boyer is incorrect, we can analyze each statement provided.

### Step-by-Step Solution:

1. **Identify the First Statement**:
- The first statement claims that Cohen and Boyer discovered recombinant DNA (rDNA) technology, which marked the birth of modern biotechnology.
- **Analysis**: This statement is true. Cohen and Boyer are indeed credited with the development of rDNA technology.

2. **Identify the Second Statement**:
- The second statement mentions that they were the first to produce the healthy sheep clone, Dolly, from differentiated adult mammary cells.
- **Analysis**: This statement is incorrect. Dolly the sheep was cloned by Ian Wilmut and his team, not by Cohen and Boyer. Therefore, this is the wrong statement.

3. **Identify the Third Statement**:
- The third statement states that they invented genetic engineering by combining a piece of foreign DNA containing a gene from a bacterium with an E. coli plasmid using restriction endonucleases.
- **Analysis**: This statement is true. Cohen and Boyer did indeed use restriction endonucleases to combine foreign DNA with plasmid DNA.

4. **Identify the Fourth Statement**:
- The fourth statement claims that they isolated an antibiotic-resistant gene by cutting a piece of DNA from the plasmid responsible for confirming antibiotic resistance.
- **Analysis**: This statement is also true. Cohen and Boyer worked with plasmids that contained antibiotic resistance genes, which served as markers in their experiments.

### Conclusion:
The incorrect statement is the second one, which attributes the cloning of Dolly the sheep to Stanley Cohen and Herbert Boyer.

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