Y-chromosome was first identified by

Options

A. Henking
B. Barr and Bertram
C. Stevens and wilson
D. Mc clung

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who first identified the Y-chromosome, which is a sex-determining chromosome.

2. **Identifying Key Information**: The Y-chromosome is crucial for determining male sex in many organisms, including humans.

3. **Researching Historical Context**: To answer the question, we need to know the historical figures involved in the discovery of the Y-chromosome.

4. **Identifying the Correct Answer**: According to historical records, the Y-chromosome was first identified by scientists Stevens and Wilson in the year 1905.

5. **Selecting the Correct Option**: From the options provided, the correct answer is "Stevens and Wilson."

6. **Final Answer**: Therefore, the Y-chromosome was first identified by Stevens and Wilson in 1905.

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