Concept:In livestock and animal breeding, mating between closely related individuals is known as in-breeding.
Explanation:In-breeding means mating closely related animals, for example a parent with its offspring or siblings with one another.
It is practised to preserve desirable traits, maintain uniformity, or establish a specific bloodline.
However, repeated in-breeding can increase the chance of expressing harmful recessive characteristics and may reduce vigour.
Cross breeding (option A) involves mating animals of different breeds.
Hybridization (option B) refers to crossing distinctly different species or varieties.
Out-breeding (option D) is mating unrelated or distantly related animals.
Therefore, the practice of mating closely related animals is correctly described by option C.
Answer:C. in-breeding