Role of chromosomes in sex determination was proposed by

Options

A. Sutton and Boveri
B. Henking
C. Mc clung
D. Morgan

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about who proposed the role of chromosomes in sex determination.

2. **Identifying Chromosomes Involved**: In humans, sex is determined by two types of sex chromosomes: X and Y. Males typically have one X and one Y chromosome (XY), while females have two X chromosomes (XX).

3. **Historical Context**: The concept of chromosomes playing a role in sex determination began to take shape in the late 19th century.

4. **Initial Research**: The initial research into the role of chromosomes in sex determination was conducted by a scientist named H. J. H. Hanking in 1891. He started experiments that contributed to the understanding of sex chromosomes.

5. **Confirmation of Findings**: Although Hanking initiated the research, it was later confirmed by another scientist, McClung, who provided evidence that the X and Y chromosomes are indeed responsible for determining sex in organisms.

6. **Conclusion**: Therefore, the correct answer to the question is that the role of chromosomes in sex determination was proposed by McClung.

### Final Answer:
The role of chromosomes in sex determination was proposed by McClung.

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