Nevermind How does the presence of an iridium layer around 64.5 million years old, support the asteroid impact theory of mass extinction at the end of the Mesozoic Era?

c

explanation:

the answer is lactic acid from anaerobic respiration. the acid in lactic acid is what creates sore and burning muscles. if you think about how acid burns that will give you a clue for questions like this.

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).   so the answer is a.