Flemming, Chain and Florey were awarded the Nobel Prize in 1945 for the discovery of

Options

A. HIV
B. CT scan
C. Penicillin
D. Staphylococcus

Answer

**Step-by-Step Solution:**

1. **Identify the Scientists**: The question mentions three scientists: Sir Alexander Fleming, Howard Florey, and Ernst Boris Chain.

2. **Nobel Prize Year**: The Nobel Prize was awarded to these scientists in the year 1945.

3. **Discovery Focus**: The main focus of their work was on antibiotics, specifically the discovery of penicillin.

4. **Source of Penicillin**: Penicillin is derived from the mold Penicillium, which was found to have antibacterial properties.

5. **Significance of Penicillin**: The discovery of penicillin was groundbreaking as it was one of the first antibiotics used to treat bacterial infections, significantly impacting medicine and public health.

6. **Eliminate Incorrect Options**:
- HIV: Discovered in the 1980s by Luc Montagnier and his team, not by Fleming, Chain, and Florey.
- CT Scan: Developed by Godfrey Hounsfield, unrelated to the work of the three scientists.
- Staphylococcus: While they studied the effects of penicillin on Staphylococcus bacteria, the discovery of Staphylococcus itself was made by Alexander Oxton.

7. **Conclusion**: Based on the information, the correct answer to the question is that Fleming, Chain, and Florey were awarded the Nobel Prize in 1945 for the discovery of penicillin.

**Final Answer**: Penicillin

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