According to Theory,studying Historical Stock Price Movements to Identify Mispriced

According to theory,studying historical stock price movements to identify mispriced stocks:

A) is effective as long as the market is only semistrong form efficient.
B) is effective provided the market is only weak form efficient.
C) is ineffective even when the market is only weak form efficient.
D) becomes ineffective as soon as the market gains semistrong form efficiency.
E) is ineffective only in strong form efficient markets.