原题
录音 1
What does the speaker imply about extrinsic rewards?
AThey are more likely to work with adults than with children.
BThey were favored by David Premack for their simplicity.
CThey do not maintain their attractiveness over the long term.
DThey usually do not produce immediate results.
正确答案：C
解题思路
老师暂未填写解题思路。