A large island in the Pacific Ocean supports isolated populations of two groups of frogs. The following observations of these
frogs were recorded by scientists.
(A) Are different in color
(B) Excrete different products
(C) Live in different, isolated habitats
(D) Can interbreed and produce fertile offspring
Which observation best supports the inference that these frogs belong to the same species?
A. A
B. B
C. C
D. D