Scientist first to isolate streptomycin was

Options

A. Fleming
B. Koch
C. Burkholder
D. Waksman

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the scientist who was the first to isolate streptomycin, an important antibiotic.

2. **Reviewing the Options**: The options provided are:
- A) Fleming
- B) Koch
- C) Burkholder
- D) Wexman

3. **Analyzing Each Option**:
- **Option A: Fleming** - Alexander Fleming is known for discovering penicillin, not streptomycin. Thus, this option is incorrect.
- **Option B: Koch** - Robert Koch is famous for his work on anthrax and discovering the causative agent of tuberculosis. He did not isolate streptomycin, making this option incorrect.
- **Option C: Burkholder** - Burkholder is recognized for his work on plant pathogens and bacteria, but he is not associated with the discovery of streptomycin. Therefore, this option is also incorrect.
- **Option D: Wexman** - Selman Wexman is credited with the discovery of streptomycin in 1943 and was awarded the Nobel Prize in Physiology or Medicine in 1952 for this achievement. This makes this option the correct answer.

4. **Conclusion**: The scientist who first isolated streptomycin is Selman Wexman (Option D).

**Final Answer**: D) Wexman

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