Since darwin's time, scientists have studied genes and gene function in a wide variety of organisms. what type of evidence for evolution is provided by data from these studies?

a. inconclusive evidence, because the genes of ancient species cannot be studied
b. inconclusive evidence, because scientists have not yet related genes to physical traits
c. weak evidence, because evolution involves changes only to body shape and body functions
d. very strong evidence, because of homologous genes and the overwhelming similarities in the genetic code