问题如下：
Following are some types of portfolio management. If the market is weak-form efficient but semi-strong-form inefficient, which of these types is most likely to earn an abnormal return?
选项：
A.Active portfolio management by using technical analysis.
B.Passive portfolio management.
C.Active portfolio management by using fundamental analysis.
解释：
C is correct.
In a semi-strong-form inefficient market, fundamental analysis is able to help analysts to earn abnormal returns by using publicly available information to identify misvalued securities. If the market is weak-form efficient, technical analysis is not able to earn abnormal returns. If the market is semi-strong-form efficient, passive portfolio would outperform fundamental analysis.
请问这道题是weak-form的情况下，为什么c选项的active trading还能获得超额收益？
