Epigenetic theory posits that most human traits are genetic; only a few can be influenced by the environment

According to Thorndike's law of effect, a subject will repeat a behavior if

a. it is intrinsically motivating. b. it offers pleasant consequences. c. a reflex response is elicited. d. the stimulus is strong enough.

Nearly ____ of pregnancies end in miscarriages

a. one-fourth c. one half b. one-third d. two-thirds