Mendel failed to get linkage because

Options

A. genes of seven types of traits selected by him were located on four different chromosomes and behaved independently
B. genes selected by him were discrete and stable
C. genes selected by him were located on seven non homologous chromosomes
D. pea plant does not show linkage

Explanation

### Step-by-Step Solution:

1. **Understanding Mendel's Work**: Gregor Mendel, known as the father of genetics, conducted experiments using the pea plant (Pisum sativum) to study inheritance patterns. He focused on seven contrasting traits such as height, color, and shape.

2. **Mendel's Laws**: From his experiments, Mendel formulated two key laws:
- **Law of Dominance**: In a heterozygous condition, the dominant trait will mask the expression of the recessive trait. For example, if T represents tallness and t represents dwarfness, the presence of T will result in a tall plant.
- **Law of Independent Assortment**: This law states that the alleles for different traits segregate independently of one another during gamete formation. This means that the inheritance of one trait does not influence the inheritance of another trait.

3. **Linkage Explanation**: Mendel did not observe linkage because the traits he studied were located on different chromosomes. Linkage refers to the tendency of genes located close together on the same chromosome to be inherited together. Since the traits Mendel examined segregated independently, it indicated that they were not linked.

4. **Conclusion**: Mendel's failure to observe linkage was due to the fact that he selected traits that were located on different chromosomes, allowing them to assort independently. This is why he concluded that traits behaved independently and did not show linkage.

### Final Answer:
Mendel failed to get linkage because the genes for the seven traits he studied were located on different chromosomes, allowing them to assort independently.

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