The rough-skinned newt produces one of the most potent toxins on the planet.Scientists in Oregon have found that as newts evolve to produce a more deadly toxin,their primary predator,the garter snake,evolves ways to resist the toxin.This is an example of
A) ecological trade-offs in the evolution of the newt.
B) an adaptation of the newt to living in aquatic environments.
C) reproductive isolation in a population of garter snakes.
D) coevolution of predator and prey.