If a Population of Butterflies Is Under Strong Natural Selection

Multiple Choice

If a population of butterflies is under strong natural selection favoring large wings but there is no genetic variation for wing size, what do we expect to occur in the next generation?

A) Wings will evolve to be smaller.
B) There will be no evolutionary change in wing size.
C) Wings will evolve to be larger.
D) Wings will evolve to be more variable.