Professor Faulpelz Asks a Random Sample of High School Freshmen

Multiple Choice

Professor Faulpelz asks a random sample of high school freshmen about their TV viewing habits. Four years later, he obtains their final high school grade-point averages and compares these with the answers about TV viewing habits. He finds that students who watch a lot of TV get lower grades than those who don't. When it comes to high school GPA, the answers to the Faulpelz questionnaire on TV viewing habits:

A) have predictive validity.
B) are invalid because they are biased against students whose parents watch TV a lot.
C) are invalid because there were no controls.
D) are invalid because of convenience sampling.