Respuesta :
They are genetically different, so they can no longer interbreed. The answer is the A. (Marked correct on the test.)
Answer: A) The population became adapted to different environments and eventually become so different that they cannot interbreed to produce fertile offspring.
According to the given situation, the canyon is a geographical barrier between the two populations. The separation of the species of squirrel has resulted in the speciation because both of the populations have adapted according to the surrounding environments. The members of the separated populations have evolved in such as manner that they are incapable of inbreeding due physical, and biological barriers, as consequence of speciation.
