Who has discovered DNA?

Options

A. Prof. Khurana
B. Prof. Chandra Shekhar
C. Dalton
D. Watson & Crick

Explanation

**Step-by-Step Solution:**

1. **Understanding DNA**: Begin by defining DNA. DNA stands for deoxyribonucleic acid, which is the genetic material found in most organisms.

2. **Identifying the Discoverers**: The question asks about the discovery of DNA. It is important to know who contributed to this discovery.

3. **Analyzing the Options**: The options provided are:
- A) Professor Khurana
- B) Professor Chandrasekhar
- C) Dalton
- D) Watson and Crick

4. **Evaluating Each Option**:
- **Professor Khurana**: He is not associated with the discovery of DNA.
- **Professor Chandrasekhar**: He is also not related to the discovery of DNA.
- **Dalton**: He is known for his work in atomic theory, not DNA.
- **Watson and Crick**: These two scientists are credited with discovering the structure of DNA.

5. **Conclusion**: Based on the evaluation, the correct answer is D) Watson and Crick.

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