What is the main cause of unhappiness for many Americans in the authors view？A．The energy

What is the main cause of unhappiness for many Americans in the authors view？

A．The energy and the genius are always confined by someone.

B．Lack of freedom and stimuli makes people unsatisfied with life.

C．People are obsessed by the thought of getting ahead of their neighbors.

D．People tend to act on dubious principles.

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