A Population of Plants Experiences Divergence as a Result of a Newly

Multiple Choice

A population of plants experiences divergence as a result of a newly established environmental gradient. Although there is not a geographic barrier, reproduction between the two populations is increasingly rare and a hybrid zone has clearly established. As speciation continues, the hybrids experience lower and lower fecundity, and, increasingly, seeds that are produced by the hybrids are sterile. This is an example of what process?

A) reproductive character displacement
B) Dobzhansky-Muller incompatibility
C) secondary reinforcement
D) allopatric speciation