The period of the embryo ends at about week _____ of gestation, when the _____ first appear

Davitz (1952) first frustrated children by stopping a great movie and taking away their candy, and then observed the children during free play. He found that children _______ were _______ aggressive than the others.

A) who saw the prosocial movie; less B) taught constructive ways to relate; less C) with short attention spans; more D) who came from abusive homes; more E) saw the whole movie; more

Random assignment:

a. eliminates differences among people b. ensures research participants do not know one another c. does not eliminate differences among people d. ensures research participants know one another