1. Which is true? Trading on inside information would not yield excess returns to investors if the stock market:

a. were efficient according to the weak form of market efficiency, but not efficient according to either the semistrong form or the strong form of market efficiency.

b. were efficient according to the weak form of market efficiency and the semistrong form of market efficiency, but not efficient according to the strong form of market efficiency.

c. were not efficient according to any of the weak form, semistrong form, or strong form of market efficiency.

d. were efficient according to all of the weak form, semistrong form, or strong form of market efficiencies.