A seems most likely, check with others if u have the time
Have a single ancestor in common.
The theory of common descent is the theory that every species evolved from one single species.
The gene frequency is affected by natural disaster as populations in which a certain allele is frequent may be wiped out. Consider a population of iguana living in forested areas, which are adapted to camouflage in their surroundings. If a forest fire were to break out and wipe out this population, the allele for such skin pigmentation would be reduced and other phenotypes would become more common.<span />
True, a salamander is an amphibian.