单项选择题
A．are directly related to pleasure B．will meet their physical needs C．will bring them a feeling of success D．will satisfy their curiosity
A．have the lights turned on B．be rewarded with milk C．please their parents D．be praised
A．a basic human desire to understand and control the world B．the satisfaction of certain physiological needs C．their strong desire to solve complex problems D．a fundamental human urge to display their learned skills