According to [ Select ] ----> ["weak", "strong", "semistrong"] form of efficiency, prices reflect all information, including public and private.

If the market is this-type form efficient, then investors [ Select] -----> ["could not", "could"] earn abnormal returns regardless of the information they possessed.

Empirical evidence indicates that markets are not this-type form efficient because insiders [ Select ] ------> ["could", "could not"] earn abnormal returns.