Stock A's beta is 1.7 and Stock B's beta is 0.7. Which of the following statements must be true about these securities? (Assume market equilibrium.) a. Stock B must be a more desirable addition to a portfolio than A. b. Stock A must be a more desirable addition to a portfolio than B. c. The expected return on Stock A should be greater than that on B. d. The expected return on Stock B should be greater than that on A.