What was the source of first induced mutations ?

Options

A. gamma ray
B. uv irradiation
C. x ray
D. cosmic rays

Answer

**Step-by-Step Solution:**

1. **Understanding Induced Mutations:**
- Induced mutations are changes in the DNA sequence that are caused by external factors, as opposed to spontaneous mutations which occur naturally.

2. **Identifying the Source of First Induced Mutations:**
- The question asks for the source of the first induced mutations. To answer this, we need to look at historical experiments that led to the discovery of induced mutations.

3. **Historical Context:**
- The first successful experiments that demonstrated induced mutations were conducted by Hermann Joseph Muller in the early 20th century.

4. **Experimental Method:**
- Muller treated the fruit fly Drosophila melanogaster with a specific type of radiation to induce mutations.

5. **Type of Radiation Used:**
- The type of radiation that Muller used to induce these mutations was X-rays.

6. **Conclusion:**
- Based on this historical context and the experimental method used, the correct answer to the question is option C: X-rays.

**Final Answer:**
The source of the first induced mutations was X-rays.

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