What is the main idea of the passage?A.American firms are different from Japanese and Germ

What is the main idea of the passage？

A．American firms are different from Japanese and German firms in human resource management.

B．Extensive retraining is indispensable to effective human resource management.

C．The head of human resource management must be in the central position in a firm"s hierarchy.

D．The human resource management strategies of American firms affect their competitive capacity.

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