While Out Dancing, Leslie Met Some New Friends

While out dancing, Leslie met some new friends. Over the past few weeks she has partaken in cocaine toward the end of the afterhours party. The first time she experienced the drug (two weeks ago) , she felt the strong rush after snorting one line; now Leslie needs to snort three lines to feel the same effect. This illustrates

A) overdose.
B) tolerance.
C) physical dependence.
D) psychological dependence.