Answer:
Polygenic traits are controlled by a number of separate genes.
Hope it helps! :D
Angiosperms have a vascular system and can live is harsher environments which means they can reproduce a lot more often and faster.
There is no answer that is right except for C. Natural Selection.
Genetic Recombination doesn't change gene frequency;nor does migration. (Unless it's local)
Mutation could be the answer, but since mutations are too rare to really power Evolution, the only logical answer is Natural Selection.
