A.        If the correlation between two stocks is over-estimated, their estimated weights in the tangency portfolio will be too high.
B.        A passive investment manager forms views over individual stocks that may differ from those of the market and uses these to find the optimal portfolio.
C.        The theory of portfolio optimization is incorrect since it leads to portfolio that have extreme weights.
D.        For active portfolio management to be successful, the manager must have better information than the market about future investment performance.
E.        Historical sample mean returns contain no information about future expected returns.