To Examine the Value of Looking at Old Tests, Professor

Multiple Choice

To examine the value of looking at old tests, Professor King hands out copies of old tests to the first 20 students who come to class one day. Later she finds that these students got better grades than the other students in the class. What is wrong with this experiment?

A) It was triple blind.
B) There is a lack of random assignment to groups.
C) There is a lack of demand characteristics.
D) The Clever Hans effect occurs.