Scenario II It Is Challenging to Conclusively Demonstrate the Effectiveness of Treatments

Scenario II
It is challenging to conclusively demonstrate the effectiveness of treatments for psychological disorders. Although treatments may appear to work, their apparent effectiveness could be due to a number of other factors, termed treatment illusions. Treatments may appear effective due to natural improvement unrelated to the treatment, placebo effects in which the apparent effectiveness of a treatment is due to the expectancy of its effectiveness, and reconstructive memory in which persons remember their symptoms prior to treatment as more severe than they were.
-(Scenario II) A research psychiatrist is studying the effectiveness of a new drug to treat insomnia. Patients with the disorder are studied in a sleep laboratory for one week before the study begins, and the time to fall asleep and the amount of time in each stage of sleep is recorded. Then they are given the experimental drug each evening and studied in the sleep laboratory for another week. At the end of the study, symptoms of insomnia lessened considerably. Unfortunately, the apparent treatment effectiveness could be due to all of these things EXCEPT:

A) natural improvement.
B) effects of reconstructive memory.
C) placebo effects.
D) the treatment was effective.