Kochanska and Her Colleagues Probably Chose to Study Toddlers' Compliance

Kochanska and her colleagues probably chose to study toddlers' compliance with their mothers' requests with the methodology they used because

A) children tend to feel most comfortable in their own homes.
B) they wanted all children to be exposed to identical situations.
C) they were interested in children's subjective experience of the event.
D) of all of these factors.