All of the Following Statements About the Sensitivity of Human

All of the following statements about the sensitivity of human sleep patterns to environmental cues such as lightness and darkness are true EXCEPT that:

A) treatment of circadian rhythm disorders often includes bright light therapy.
B) people in rural areas tend to have circadian rhythms that match natural sunrise-sunset patterns.
C) people in urban areas tend to have circadian rhythms that match natural sunrise-sunset patterns.
D) circadian rhythm responds to light-producing stimuli in day-to-day life.