What is the most popular method of testing ideas in social psychology?

Which of the following children is most likely to be diagnosed with type II diabetes?

a) Carlos, a Hispanic American child of high socioeconomic status b) Alex, a Caucasian child of low socioeconomic status c) Darryl, an African American child of moderate socioeconomic status d) Sherman, a Native American child of low socioeconomic status

DeCasper and Fifer used _____ as the dependent variable to test if two-day-old infants could identify the sound of the mother's voice

A) ?eye movements B) ?head tilts C) ?pattern of nipple sucking D) ?eye blinks