能不能解释一下这题

问题如下：

If securities markets are semi-strong-form efficient, the most appropriate role of a portfolio manager is to:

选项：

A.invest by analyzing publicly available information to consistently generate abnormal returns.

B.manage portfolios with appropriate diversification and asset allocation, taking into consideration investor preferences.

C.exploit appropriate trading rules and serial correlations for achieving excess returns.

解释：

1. Incorrect. The semi-strong-form efficiency assumes that prices reflect all publicly known and available information, and therefore efforts to analyze publicly available information is futile.

2. Correct. If markets are semi-strong-form efficient (which also encompasses weak-form efficiency), the role of a portfolio manager is not necessarily to beat the market, but rather to establish and manage a portfolio consistent with the portfolio’s objectives, with appropriate diversification and asset allocation, while taking into consideration the risk preferences and tax situation of the investor.

3. Incorrect. Exploiting trading rules and serial correlations would not be feasible if markets are weak-form efficient, leave alone semi-strong-form efficiency.

• explain the implications of each form of market efficiency for fundamental analysis, technical analysis, and the choice between active and passive portfolio management