Genes located on Y-chromosome are

Options

A. mutant genes
B. sex-linked genes
C. autosomal genes
D. holandric genes

Explanation

To answer the question "Genes located on Y-chromosome are", we need to analyze the options provided and understand the characteristics of the Y-chromosome.

### Step-by-Step Solution:

1. **Understanding Y-Chromosome**: The Y-chromosome is one of the two sex chromosomes in humans (the other being the X-chromosome). It is responsible for determining male sex characteristics.

2. **Identifying Types of Genes**:
- **Mutant Genes**: These are genes that have undergone mutation, which is a change in the DNA sequence. This term does not specifically relate to the Y-chromosome.
- **Sex-linked Genes**: These are genes located on sex chromosomes (X or Y). Thus, genes on the Y-chromosome can be considered sex-linked.
- **Autosomal Genes**: These are genes located on autosomes, which are non-sex chromosomes. The Y-chromosome is not an autosome.
- **Holandric Genes**: These are genes that are located exclusively on the Y-chromosome and are passed from father to son.

3. **Choosing the Most Appropriate Answer**:
- While Y-chromosome genes are indeed sex-linked, the most precise term for genes located specifically on the Y-chromosome is "holandric genes". Therefore, the most appropriate answer is "holandric genes".

### Final Answer:
Genes located on Y-chromosome are **holandric genes**.

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