Which Study Illustrates a Nonexperimental Study

Multiple Choice

Which study illustrates a nonexperimental study?

A) A study comparing self-esteem scores for children with a learning disability versus scores for children without a learning disability
B) A study comparing depression scores for one group that is assigned to receive a therapy versus another group that is assigned not to receive a therapy
C) A study comparing performance in a room where the walls have been painted yellow versus performance in a room painted blue
D) A study comparing cognitive functioning scores for one group of Alzheimer's patients who are assigned to receive memory therapy versus another group that is assigned not to receive therapy