A Researcher, Based on His Review of Relevant Scientific Studies

Essay

A researcher, based on his review of relevant scientific studies, believes that there is a relationship between the frequency of a baby's crying and whether it was nursed at set intervals or on a demand schedule. If this belief were tested by experimentally manipulating feeding schedules, the feeding schedule would be called the:
a. independent variable.
b. dependent variable.
c. extraneous variable.
d. control factors.