What Evidence Exists in the Predator-Prey Relationship of Rough-Skinned Newts

What evidence exists in the predator-prey relationship of rough-skinned newts (predator) and garter snakes (prey) for the evolution of variation in toxicity in rough-skinned newts and resistance to toxicity in garter snakes? Scientists have observed that ________.

A) After unusually cold winter temperatures five years in a row, rough-skinned newts needed a mutation to increase levels of neurotoxicity, so they evolved it, while garter snakes needed a mutation to increase levels of resistance to that neurotoxin, so they evolved it.
B) Over many generations of random mutation and nonrandom natural selection, rough-skinned newts needed a mutation to increase levels of neurotoxicity, so they evolved it, while garter snakes needed a mutation to increase levels of resistance to that neurotoxin, so they evolved it.
C) After one generation of random mutation, rough-skinned newts with greater and greater neurotoxicity were selected for, while garter snakes with greater and greater resistance to that neurotoxin were selected for.
D) Over many generations of random mutation and nonrandom natural selection, rough-skinned newts with increasing levels of neurotoxicity were selected for, while garter snakes with increasing levels of resistance to that neurotoxin were selected for.