Which of the following statements does NOT describe the role of a portfolio manager in perfectly efficient markets Portfolio managers should:（）

A. construct diversified portfolios that include international securities to eliminate unsystematic risk.

B. quantify client’s risk tolerance, communicate portfolio policies and strategies, and maintain a strict buy and hold policy avoiding any changes in the portfolio to minimize transaction costs.

C. help clients minimize taxes and reduce trading turnover.

盘查技巧中的“四看四对”即：看证件、对姓名、看籍贯、对口音，看物品、对来由，看同伴、对关系。