Uplift and Formation of a Mountain Range Divide a Freshwater

Multiple Choice

Uplift and formation of a mountain range divide a freshwater snail species into two isolated populations. Erosion eventually lowers the mountain range and brings the two populations together again, but when they mate, the resulting hybrids all produce sterile young. This scenario is an example of

A) sympatric speciation.
B) allopatric speciation.
C) incomplete speciation.
D) diversifying speciation.