当一个不爱学习的学生表现出良好的学习行为时，老师撤消对他的批评，老师的这一做法属于（）
A. 消退
B. 惩罚
C. 负强化
D. 正强化
查看答案
Which of the following is the patients entitled to do in terms of the proposal？
A. Be honest to their doctors.
B. Control their medical information.
C. Determine how to make their medical, records.
D. Accuse the insurers of making use of their medical data.
When must you pay for the ticket？
At any time before the trip.
B. One week before the trip.
C. Three days before the trip.
With which of the following would the author be LEAST likely to agree？
A. Children naturally and easily learn mathematics.
B. Children learn to add before they learn to subtract.
C. Most people follow the same pattern of mathematical development.
D. Mathematical development is subtle and gradual.
What did the police do to find Carol？
A. They asked Gerard Croiset for help.
B. The let people see her pictures.
C. They put her pictures in newspapers.
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