The year 2003 was celebrated as the `50^(th)` anniversary of discovery of

Options

A. transponsons by Barbara Mc Cliontock
B. structure of DNA by Watson and Crick
C. Mendel's laws of inheritance
D. biotechnology by Kary Mullis.

Explanation

**Step-by-Step Solution:**

1. **Identify the Year of Celebration**: The question states that the year 2003 was celebrated for a significant discovery. We need to determine what discovery was being celebrated.

2. **Determine the Anniversary**: The question mentions the "50th anniversary." To find the original year of the discovery, we subtract 50 from 2003.
- Calculation: 2003 - 50 = 1953.

3. **Identify the Discovery in 1953**: In 1953, James Watson and Francis Crick proposed the double helix structure of DNA. This was a pivotal moment in the field of genetics.

4. **Confirm the Contribution of Others**: It is important to note that other scientists, such as Rosalind Franklin and Maurice Wilkins, contributed to this discovery through X-ray diffraction techniques, which provided crucial data for Watson and Crick's model.

5. **Recognize the Significance**: The discovery of the DNA double helix structure was a turning point in genetics and molecular biology, leading to advancements in understanding heredity and genetic information.

6. **Nobel Prize Recognition**: Watson, Crick, and Wilkins were awarded the Nobel Prize in Physiology or Medicine in 1962 for their contributions to the understanding of DNA.

7. **Conclusion**: Therefore, the correct answer to the question is that the year 2003 celebrated the 50th anniversary of the discovery of the DNA double helix structure by Watson and Crick.

**Final Answer**: The year 2003 was celebrated as the 50th anniversary of the discovery of the DNA double helix structure by Watson and Crick.

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