When Paige went to college she decided to test her cognitive hypothesis related to the above scenario. She predicted that 3 hours of (NIGHT) studying for three days before your math exam will yield a better score than 3 hours of (DAY) studying three days before your exam. In this experimental design scenario, since hours of study and number of days of studying before the exam are held constant, what would be your independent variable and dependent variable, respectively?

A. Type of teacher - independent variable / score - dependent variable
B. Hours of study - independent variable / score - dependent variable
C. Time of study (day or night) - independent variable / score - dependent variable
D. Time of study (day or night) - dependent variable / score - independent variable