A psychologist is interested in the relationship between the number of times a baby is held during a day and how often the baby cries. The psychologists observe several day care centers where infants are being cared for and record the number of times each baby is held and the number of times each baby cries throughout the day. The data shows that babies who are held more tend to cry less. Scenario C involves which scientific method?
A. Retrospective study
B. Correlational method
C. Controlled experiment
D. Prospective study