Christopher used to drink water from a drinking fountain just before physics class. One time, he felt nauseated right after drinking the water. After that, to avoid the risk of nausea, he stopped...

Christopher used to drink water from a drinking fountain

just before physics class. One time, he felt nauseated right

after drinking the water. After that, to avoid the risk of

nausea, he stopped drinking at the fountain. Christopher

learned a connection between the water fountain and

feeling nauseated because he experienced ______.
a) acquisition
b) extinction
c) spontaneous recovery
d) counterconditioning