When the inherited blood types of mother and fetus differ, the most common cause of difficulties is

Any difference between experimental and control groups other than the independent variable is a ________ variable.

a. confounding b. false c. dependent d. placebo

Kenneth tends to watch a lot of television violence; he frequently gets in trouble at school and at home. Kenneth lies to get himself out of trouble

He does not feel bad when he verbally or physically hurts someone, but instead insists, "It wasn't my fault; he asked for it." Kenneth is a a. scapegoat. c. bully. b. loner. d. brat.