What defines a group of interbreeding individuals that are reproductively isolated from other such groups?

a. ecological species

b. phylogenetic species

c. biological species

d. homologous species

Biological species.

Explanation:

Various concept like morphology species concept, ecological species concept was introduced by the scientists to explain the biological species. The biological species concept is accepted today.

The biological species concept explains that the group of interbreeding population that has the ability to reproductively isolated from the other such group.

Thus, the correct answer is option (c).