H.J. Muller ws awarded Nobel Prize for

Options

A. Protein synthesis
B. Chemistry of nucleic acids
C. Cancer
D. X-ray induced mutations

Answer

**Step-by-Step Solution:**

1. **Identify the Subject**: The question asks about H.J. Muller and the reason he was awarded the Nobel Prize.

2. **Review the Options**: The options provided are:
- a) Protein synthesis
- b) Chemistry of the nucleic acid
- c) Cancer
- d) X-ray induced mutation

3. **Recall Historical Context**: H.J. Muller is known for his work in genetics and mutagenesis. His significant contributions were made in the early 20th century.

4. **Focus on Key Contributions**: In 1926, Muller conducted experiments to test the effects of X-rays as a mutagen. He bred fruit flies (Drosophila melanogaster) that had specific genetic markers on their X chromosomes, which allowed him to identify mutations.

5. **Conclusion**: Based on his experiments and findings, H.J. Muller was awarded the Nobel Prize in Physiology or Medicine in 1946 for his discovery of X-ray induced mutations.

6. **Final Answer**: Therefore, the correct option is **d) X-ray induced mutation**.

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