The common garter snake is a predator of the rough-skinned newt. Over time, the rough-skinned newt began producing tetrodotoxin, a substance toxic to...

The common garter snake is a predator of the rough-skinned newt. Over time, the rough-skinned newt began producing tetrodotoxin, a substance toxic to the garter snake. Recently, scientists have found garters that are able to eat rough-skinned newts because the snakes contain a chemical that confers tetrodotoxin resistance. The finding of tetrodotoxin-resistant garter snakes is an example of which of the following?

 A. ecological succession

 B. environmental stress

 C. natural selection

 D. planned breeding programs