A fellow student asks, "How is it possible that six feet of DNA can fit inside a single, microscopic nucleus of a cell?" Let's draw a parallel to help explain. If you were to unravel a ball of yarn, it would
probably be able to circle around your house (that's a long distance!). Use this comparison to answer
your fellow student's question.

Which of the following factors would not contribute to allopatric speciation? a) a population becomes geographically isolated from the parent population.b) the separated population is small, and genetic drift occurs.c) the isolated population is exposed to different selection pressures than the ancestral population.d) different mutations begin to distinguish the gene pools of the separated populations.e) gene flow between the two populations is extensive.