You are holding stock A and would like to include B, C, or D to form an equal-weighted portfolio, AB, AC, or AD. A and B are negatively correlated; A and C are positively correlated; and A and D are uncorrelated (i.e., 0 correlation).

Rank the standard deviations of the portfolios, AB, AC, and AD, in a descending order (the highest in the front): [Assume all the stocks have the same standard deviation.]

AC,AD,AB

AC,AB,AD

AB,AD,AC

AD,AB,AC

AB,AC,AD

AD, AC,AB