What is the biggest difference between the Geocentric and Heliocentric Model? *

The shape of the planets' orbits
The movement of the moon
The center of the solar system

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.