Areproductive barrier that prevents species from mating is an example of reduced hybrid fertility reduced hybrid viability a post-zygotic barrier zygote mortality a pre-zygotic barrier

a = executive branch; b = judicial branch

all these collisions do one thing, and that thing is explained in the last option. when dusst, rocks and ice collide, they harden and form giant layers of rocks or hard ice.

d)   to harden materials to form different parts of earth’s layers

hope it ,

bioteacher101