Chromosome banding was discovered by

Options

A. Casperson et al
B. Muller
C. Berg et al
D. Christian de Duve

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the discovery of chromosome banding, which is a technique used to identify chromosomes based on their distinct banding patterns.

2. **Identifying the Options**: The options provided are:
- A) Caspersen et al
- B) Muller
- C) Berg et al
- D) Christian D. Duwe

3. **Recalling the Discovery**: Chromosome banding was first discovered in 1968. It is important to remember the key figures associated with this discovery.

4. **Analyzing the Options**:
- **A) Caspersen et al**: This is the correct answer as they discovered chromosome banding in the plant species Vicia faba.
- **B) Muller**: This option is incorrect; he is not associated with the discovery of chromosome banding.
- **C) Berg et al**: This option is also incorrect; they did not discover chromosome banding.
- **D) Christian D. Duwe**: This option is incorrect as well; he is not known for this discovery.

5. **Conclusion**: Based on the analysis, the correct answer to the question "Chromosome banding was discovered by" is **A) Caspersen et al**.

**Final Answer**: A) Caspersen et al

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