What prevents the results of a single case study from being applied to many people?

At what age do children start to show fear when a new person enters their environment?

A. at birth B. by 3 months C. by 6 months D. by 9 months

Joseph Goebbels, Hitler's propaganda minister, used a technique he called "The Big Lie." He knew that people begin to believe that a statement is true simply because it has been repeated a number of times. The formal name for this technique is ________

a. the validity effect. b. groupthink. c. diffusion of responsibility. d. symbolic racism.