Samantha Signs Up for a Psychology Experiment and Is Told

Multiple Choice

Samantha signs up for a psychology experiment and is told that the study involves people's study habits by themselves or in groups.She is assigned to an individual study room and given a packet of materials to study.She also notices that she can hear music through speakers in the room and wonders whether the experiment is really about whether music distracts people while they are studying.She decides to try even harder to study the material she was given and ignore the music.This example best demonstrates the concept of

A) the Rosenthal effect.
B) demand characteristics.
C) experimenter expectancy effects.
D) the placebo effect.