In a Coevolutionary Arms Race, After a Plant Evolves a Novel

In a coevolutionary arms race, after a plant evolves a novel chemical defense against an herbivore,

A) the herbivore can be expected to go extinct.
B) the herbivore can be expected to disperse to new habitats.
C) the herbivore can be expected to evolve resistance to the plant's defense.
D) the plant can be expected to colonize new habitats.
E) the plant can be expected to outcompete all other plants in the same environment.