In a Longitudinal Study on the Consistency of Self-Control, Researchers

In a longitudinal study on the consistency of self-control, researchers found that

A) for boys, aggression at 2 years was related to acting out at 4 years.
B) most children were more aggressive and less self-controlled at 4 than at 2 years.
C) there were no gender differences in self-control at 2 or 4 years.
D) the correlation between aggression at 2 years and acting out at 4 years was highest for children with negative mothers.