听力原文： Research indicates that parents who reward self-control and independence tend to have children with high achievement motivation. Such parents set high standards for their children but allow them to work at their own level and to make their own mistakes. By contrast, parents of low need achievers typically set impossibly high goals for their children and make extreme demands. In addition, parents of high need achievers encourage good performance but do not scold their children when they fail. If a child comes home from school with four A's and one B on a report card, the parents focus on the A's; parents of a potential low need achiever tend to ask, "Why the B？" Parents of high need achievers respond to moderate grades with warmth and suggestions for reasonable goals and ways to reach them. Parents of low need achievers might say, "You're dumb and lazy; you'll never amount to anything." And then they punish the child. When a child is having trouble with a maths problem, the parent of a potentially high need achiever will suggest the general procedure and let the child work out the particular solution; a low need achiever's parent will solve the problem and then hand the child the answer.
That needs for achievement exist with all of us, to varying degrees, is undeniable. A great deal more is known about the psychological bases of these needs and how they come about.
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A. They usually leave their children alone.
B. They allow for failure on the part of their children.
C. They control their children to a minimum degree.
D. They set very high standards for their children.