The vaccine for smallpox was discovered by:

Options

A. Alexander Fleming
B. Edward Jenner
C. Louis Pasteur
D. Robert Koch

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks about the discovery of the vaccine for smallpox and provides four options: Alexander Fleming, Edward Jenner, Louis Pasteur, and Robert Koch.

2. **Identifying the Correct Scientist**: Among the options, we need to identify who is known for discovering the smallpox vaccine.

3. **Historical Context**: Edward Jenner is recognized for developing the smallpox vaccine in the year 1796. This was a significant milestone in the field of immunology and vaccination.

4. **Reviewing Other Options**:
- **Alexander Fleming** is known for discovering penicillin, which is an antibiotic, not a vaccine.
- **Louis Pasteur** contributed to the field of microbiology and is known for pasteurization and vaccines for rabies and anthrax.
- **Robert Koch** is famous for identifying the bacterium that causes tuberculosis.

5. **Conclusion**: Based on the historical contributions of these scientists, the correct answer to the question is Edward Jenner, who discovered the smallpox vaccine.

**Final Answer**: The vaccine for smallpox was discovered by Edward Jenner.

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