What is the ultimate source of genetic variation?

mutations

Explanation:

Mutations are changes in DNA sequence that can create genetic variation within the population and thus are the ultimate source of new alleles . Mutations are important for evolution because of their ability to form a new genetic variant (allele) that can be spread to the offspring.  If a new variant of a trait formed by a mutation is advantageous and helps the organism to survive and reproduce,  it is going to be favourable by natural selection. That  variation will more likely be passed to the next generation and remain over time.

b is dominant over the allele for the white fur.

a researcher conducts an experiment on the secretion of a particular hormone in mice. scientists inject mice with a substance that stimulates the production of the hormone. the scientists then test the levels of hormones produced by the mice. the tool used to measure the hormones consistently detects the levels at 10 points lower than the actual hormone levels in the mice. this tool makes measurements, but the measurements aren't .

explanation:

no u