Inbreeding depression is due to

Options

A. Mutation
B. Vegetative propagation
C. Cross breeding
D. Self pollination

Answer

### Step-by-Step Solution:

1. **Understanding Inbreeding**: Inbreeding refers to the mating of organisms that are closely related genetically. This can occur within a species when individuals with similar genetic backgrounds breed with each other.

2. **Definition of Inbreeding Depression**: Inbreeding depression is a phenomenon where the offspring produced from inbreeding exhibit reduced biological fitness. This can manifest as weaker individuals that may have lower survival rates, reduced fertility, or increased susceptibility to diseases.

3. **Causes of Inbreeding Depression**: The primary cause of inbreeding depression is the accumulation of deleterious (harmful) alleles. When closely related individuals breed, there is a higher chance that both parents carry the same recessive alleles, which can lead to the expression of harmful traits in the offspring.

4. **Impact on Progeny**: The progeny resulting from inbreeding often show a decline in vigor and vitality. This is because the genetic diversity is reduced, which can limit the ability of the population to adapt to environmental changes or resist diseases.

5. **Conclusion**: Inbreeding depression is primarily due to the mating of closely related individuals within the same species, leading to a decrease in the overall fitness of the progeny.

### Final Answer:
Inbreeding depression is due to the mating of closely related individuals within the same species, resulting in reduced biological fitness of the offspring.

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