Penicilin was first discovered by .

Options

A. A.Fleming
B. Tence and Salke
C. S.A. Waksna
D. Lewis Pasteur

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks who first discovered penicillin.

2. **List the Options**: The options provided are A. Fleming, B. Tansen Salk, C. S.K. Waxner, and D. Louis Pasteur.

3. **Recall Historical Context**: Penicillin is known as the first true antibiotic and has been widely used in medicine since its discovery.

4. **Identify the Correct Answer**: Penicillin was discovered by Alexander Fleming in the year 1928. He was a professor of bacteriology at St. Mary's Hospital in London.

5. **Explain the Discovery**: Fleming discovered penicillin accidentally when he noticed that a mold (later identified as Penicillium notatum) had contaminated one of his petri dishes and was killing the surrounding bacteria.

6. **Conclude**: Therefore, the correct answer to the question is A. Fleming.

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