Nicolaus and Nellis Used Classical Conditioning to Develop a Taste

Nicolaus and Nellis used classical conditioning to develop a taste aversion in mongooses.They allowed the animals to eat eggs that had been laced with carboachol, which caused the animals to become ill.Later, the mongooses showed an aversion to eggs.In this example of classical conditioning, the stomach distress after eating the carboachol was:

A) an unconditioned stimulus
B) an unconditioned response
C) a conditioned stimulus
D) a conditioned response