Answer:
Exploiting a new niche in a common location - Allopatric Speciation
Extrinsic factor prevents two or more groups from mating with each other
regularly - Sympatric Speciation
Gene flow has been reduced between flies that feed on different food varieties, even though they both live in the same geographic area - Sympatric Speciation
The gradual formation of the Grand Canyon split a population into 2 divergent
species - Allopatric Speciation