单项选择题

A.同域种化(sympatric speciation)—杂交(hybridization)
B.异域种化(sympatric speciation)—地理屏障(geographical barrier)
C.线性种化(anagenesis)—中间型化石(transitional fossil)
D.分支种化(cladogenesis)—活化石(living fossil)
E.生态种化(ecological speciation)—栖位分割(niche segregation)