Two nucleotide sequences found in two different species are almost exactly the same. This suggests that these species:
A. contain identical DNA.
B. have the same number of mutations.
C. are evolving into the same species.
D. may have similar evolutionary histories.
Comparative biochemistry shows that the more similar two species DNA is, the more closely related they are, and the more recently they evolved separately. This is evidenced in the fact that humans and apes have more than 99% similar DNA sequences!