According to Research Supporting the Overjustification Effect (E

According to research supporting the overjustification effect (e.g.,Grusec et al.,1979) ,if you want to encourage children to behave in prosocial ways toward each other,you should

A) promise them tangible rewards, like stickers, if they are nice to each other.
B) commend them and tell them how wonderful you think they are after they have been nice to each other.
C) require them to be nice to each other.
D) punish them if they do not engage in prosocial behaviours.
E) try not to interfere with their interactions.