Mustard gas was used as a chemical mutagen for the first time by

Options

A. Muller
B. Alterberg
C. Auerbach and Robinson
D. Stadler.

Answer

To answer the question "Mustard gas was used as a chemical mutagen for the first time by which scientist?", we can follow these steps:

### Step 1: Identify the Scientists
We have four scientists mentioned in the question:
1. Herman Muller
2. Alteberg
3. Orbeck and Robinson
4. Stadler

### Step 2: Analyze Each Scientist's Contribution
- **Herman Muller**: Known for his work on the hereditary characters in fruit flies, specifically studying mutations.
- **Alteberg**: A Swedish scientist who defined the limits of soil, not related to mutagens.
- **Orbeck and Robinson**: They are noted for their work involving mustard gas as a chemical mutagen.
- **Stadler**: An American geneticist who focused on the mutagenic effects of different forms of radiation.

### Step 3: Determine the Correct Answer
From the analysis, we see that Orbeck and Robinson are specifically associated with the use of mustard gas as a chemical mutagen. Therefore, they are the correct answer to the question.

### Final Answer
Mustard gas was used as a chemical mutagen for the first time by **Orbeck and Robinson**.

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