The first antibiotic was discovered by

Options

A. R. Koch
B. Louis Pasteur
C. A. Fleming
D. W. Flemming

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about the discovery of the first antibiotic.

2. **Recall Historical Context**: The first antibiotic was discovered in the early 20th century.

3. **Name the Scientist**: The scientist who discovered the first antibiotic is Alexander Fleming.

4. **Specify the Year of Discovery**: Alexander Fleming discovered penicillin in the year 1928.

5. **Describe the Impact**: The discovery of penicillin led to the introduction of antibiotics, which significantly reduced the number of deaths caused by bacterial infections.

6. **Eliminate Other Options**:
- Robert Koch is known for discovering the tubercle bacillus, not antibiotics.
- Louis Pasteur is famous for pasteurization and vaccines, not for discovering antibiotics.
- W. Fleming (not to be confused with Alexander Fleming) contributed to cell biology, not antibiotics.

7. **Conclude the Answer**: Therefore, the first antibiotic was discovered by Alexander Fleming.

**Final Answer**: The first antibiotic was discovered by Alexander Fleming.

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