Bird guides once listed the myrtle warbler and audubon's warbler as distinct species. recently, these birds have been classified as eastern and western forms of a single species, the yellow-rumped warbler. which of the following pieces of evidence, if true, would be cause for this reclassification? a) the two forms are observed to interbreed successfully where their habitats overlap. b) the two forms live in similar habitats. c) the two forms have many genes in common. d) the two forms have similar food requirements. e) the two forms are very similar in coloration.

The correct answer is A). The two forms are observed to interbreed successfully where their habitats overlap.

Explanation:

According to the biological species concept, the members in a population which interbreed with each other and produce viable offsprings comes under the same species. This classification does not involve morphology because even organisms having the same morphology can be of different species because they do not interbreed with each other in nature.

So here myrtle warbler and Audubon's warbler must be found interbreeding with each other and producing offsprings which have good survival rate and reproductive capability so this information might allowed scientists to reclassify these bird in the same species because only members of same species interbreed with each other. So the correct answer is A.