PCR technique was invented by:

Options

A. Boyer
B. Cohen
C. Sanger
D. Kary Mullis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who invented the PCR (Polymerase Chain Reaction) technique.

2. **Analyzing the Options**: The provided options are:
- A) Boyer
- B) Cohen
- C) Sanger
- D) Karimullis

3. **Evaluating Option A - Boyer**: Herbert Boyer is known for his work in genetic engineering and recombinant DNA technology, but he did not invent the PCR technique.

4. **Evaluating Option B - Cohen**: Stanley Cohen, along with Boyer, contributed to genetic engineering, but he is not associated with the invention of PCR.

5. **Evaluating Option C - Sanger**: Frederick Sanger is recognized for developing methods of DNA sequencing, which is different from PCR. Thus, he is not the correct answer.

6. **Evaluating Option D - Karimullis**: Kary Mullis is the scientist credited with inventing the PCR technique. He was awarded the Nobel Prize for this significant contribution to molecular biology.

7. **Conclusion**: Based on the evaluations, the correct answer to the question "PCR technique was invented by" is Kary Mullis.

**Final Answer**: D) Karimullis

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