Identifying The Independent Variable
Dr. Ramos is investigating the effect of exercise on productivity. He randomly assigns participants to two groups of 30. Group A performs 30 minutes of cardiovascular exercise each morning, while Group B performs no exercise. All participants then complete a series of tasks, and their productivity is measured by the number of correct tasks completed per minute. What is the independent variable in this study?
AThe number of correct tasks completed per minute
BThe presence or absence of exercise
CThe number of participants in each group
DNone of the above