Holandric traits are

Options

A. Y chromosome linked traits
B. X chromosome linked traits
C. X and Y chromosome linked traits
D. Autosomal linked trait.

Answer

**Step-by-Step Solution:**

1. **Understanding Holandric Traits**: Holandric traits are genetic traits that are specifically associated with the Y chromosome. This means that these traits are carried on the Y chromosome and are inherited through male lineage.

2. **Identifying the Chromosome**: The Y chromosome is one of the two sex chromosomes in humans (the other being the X chromosome). Holandric traits are unique because they are only found on the Y chromosome.

3. **Function of Holandric Traits**: These traits primarily code for male-specific functions, such as the development of the testes. The testes are responsible for producing testosterone, which is crucial for male development and secondary sexual characteristics.

4. **Inheritance Pattern**: Holandric traits are inherited in a specific manner; they can only be passed from father to son. This is because only males possess a Y chromosome, and thus, only they can pass these traits to their male offspring.

5. **Conclusion**: Based on the above understanding, the correct answer to the question "Holandric traits are" is that they are Y-chromosome linked traits.

**Final Answer**: Holandric traits are Y-chromosome linked traits.

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