Penicillin was discovered by :

Options

A. Alexander Fleming
B. A. F. Blakeslee
C. K. C. Mehta
D. Alexopoulos and Martin

Explanation

**Step-by-Step Solution:**

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

2. **Review the Options**: The options provided are:
- A) Alexander Fleming
- B) A. F. Blacklessie
- C) K. C. Mehta
- D) Alexopoulos and Martin

3. **Recall Historical Context**: Penicillin was discovered during a bacterial experiment.

4. **Identify the Correct Scientist**: Alexander Fleming is known for discovering penicillin. He made this discovery on March 14, 1942.

5. **Understand the Discovery Process**: While working with bacteria, Fleming isolated a mold that belonged to the genus Penicillium. This mold produced a substance that inhibited bacterial growth, which is the active component of penicillin.

6. **Conclude the Answer**: Based on the information, the correct answer is A) Alexander Fleming.

**Final Answer**: Penicillin was discovered by Alexander Fleming.

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