Apair of male holstein (black-and-white) calves that have the same parents display manysimilarities but also exhibit some variations. which process best explains these variations?

Independent assortment

Explanation:

Independent assortment law establishes that the alleles from two or more different genes distribute in gametes independently from each other. In other words, a gamete receives an allele from a gene that does not depend nor influence the allele of another gene in the same gamete. This can only be applied to independent genes.

During gamete formation in meiosis, the pairs of homologous chromosomes separate after crossing over, and then chromatids sisters also separate, resulting in the formation of four gametes. Each gamete has different information from the combination of homologous chromosomes belonging to the father an to the mother.

Many genes segregate independently after crossing-over because they are located far away from each other. But some other genes are too close and they do not segregate independently. These are the linked genes that do not exhibit an independent distribution, and they inherit together more frequently.

This is why the calves display many similarities but also exhibit some variations.

that is wrong, its not thymus.