What do biologists use to establish whether or not two organisms are of the same species?

a. comparisons of dna and proteins

b. comparisons of appearance

c. comparisons of structure

d. all of the above

D. all of the above

Explanation:

A species is a group of organisms that are capable of interbreeding to produce fertile progeny.

Organisms of the same species are usually have similar genome in form of DNA and protein. They are also similar morphological and structurally.

Hence, scientists compare DNA/protein, appearance, and structure to establish whether or not two organisms are of the same species.

The correct option is D.

answer: c

explanation: