Christopher Has Developed a Behavioral Method That He Believes Will

Multiple Choice

Christopher has developed a behavioral method that he believes will help people quit smoking.He recruits a group of 25 people who want to quit smoking and begins his intervention.By the time the intervention ends,only eight people remain,but they have all quit smoking.This is an example of a(n) ____ threat.

A) history
B) mortality
C) instrumentation
D) regression