Homozygous pure lines in cattle can be obtained by

Homozygous pure lines in cattle are achieved through inbreeding, which involves mating related individuals within the same breed. This practice increases homozygosity, leading to pure lines.

Correct Answer: d) Mating of related individuals of the same breed

Explanation: Inbreeding, the mating of closely related individuals within the same breed, increases homozygosity, resulting in pure lines. This method is commonly used in animal breeding to establish and maintain specific genetic traits.

Incorrect Options:

• a) Mating of individuals of different species: This is interspecific hybridization, not inbreeding.
• b) Mating of animals of different breeds: This is crossbreeding, which increases heterozygosity.
• c) Mating of unrelated individuals of the same breed: This is outbreeding, which also increases heterozygosity.