Variability resulting from individual differences among research subjects is referred to as

The Gardners taught Washoe a manual language

a. to eliminate confounding variables such as prosody, accent, and tone of voice. b. because chimpanzees cannot produce the variety of speech sounds that humans can. c. to provide some control over vocabulary. d. to reduce the possibility that researchers would demonstrate the meaning of a word with their hands. e. because she suffered from Wernicke's aphasia.

Lance is in the 12th grade and is presently dating the head cheerleader named Ava. Lance is attracted to Ava, who is very feminine in her mannerisms, and Lance reports that he is attracted to girls who are petite and athletic

He and his buddies like to go "cruising for girls" on the weekends but he has never strayed from Ava and is thinking about proposing to her after they graduate. He has never been attracted to any other boys. Lance is considered __________ in terms of his sexual orientation. a) homosexual b) heterosexual c) bisexual d) transexual