TOEFL Listening: TPO-TOEFL阅读TPO - FQ10ITBOOMHQL3FYN$

According to paragraph 1, allopatric speciation involves which of the following? A. The division of a population into subspecies B. The reuniting of separated populations after they have become distinct species C. The movement of a population to a new homeland D. The absence of gene flow between subpopulations