Fatima Wants to Study How Ice Cream Consumption in a School

Multiple Choice

Fatima wants to study how ice cream consumption in a school cafeteria is related to aggressive playground behaviour during recess.She realizes that lack of teacher supervision is a possible third variable that could cause both overconsumption and aggressiveness.She studies only children who have received identical amounts of supervision during the day.What technique is Fatima using to attempt to control for this third variable?

A) matched samples
B) matched pairs
C) matched supervisors
D) double-blind observation