题目内容：
The quotation in Paragraph 4 explains that_______.
A．gains of technology have been erased A．gains of technology have been erased
B．job opportunities are disappearing at a high speed
B．job opportunities are disappearing at a high speed
C．factories are making much less money than before
C．factories are making much less money than before
D．new jobs and services have been offered
D．new jobs and services have been offered
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答案解析：