DrAcitelli Studies Sleep and Sleep Disorders

Dr.Acitelli studies sleep and sleep disorders.She is curious as to whether falling asleep in front of a television set causes people to fall asleep more slowly than falling asleep without watching TV.She recruits a sample of 60 middle-aged women from a local church who reported no history of sleep problems.She creates three conditions.All participants come to the sleep lab for three nights in a row and experience all three conditions.In the first condition (A) ,participants fall asleep in front of a television that is off.In the second condition (B) ,participants fall asleep in front of a television that is turned on to the same 24-hour news channel.In the third condition (C) ,participants fall asleep in front of a television that is turned on to the same 24-hour news channel but is muted.With the use of an electroencephalograph (EEG) ,the researcher measures how long it takes participants to fall asleep.

-Given that there are three conditions/levels of the independent variable,how many orders of the conditions are possible in Dr.Acitelli's study?

A) Three
B) Six
C) Nine
D) Twelve