Three-Month-Old Infants Were Seated in an Apparatus in Which They

Three-month-old infants were seated in an apparatus in which they could see live images of their legs transmitted on two TV monitors in front of them. Different images-sometimes reversed and sometimes upside down-were presented on each monitor. Which statement is TRUE regarding this study?

A) The variable that the researchers were interested in was heart rate.
B) The babies' looking responses indicated that they knew when the timing of their leg movements did not match what was on the screen.
C) The babies did not react when the direction of the leg movements that they viewed did not match their leg movements.
D) The babies looked longer when they moved their legs but saw their arms on the screen.