EC is considering adding a mutual fund to her diversified portfolio. Which of the following is the best choice based on risk and return?

a. Mutual fund A: expected return of 12%, beta of 1.3.

b. Mutual fund B: expected return of 14%, beta of 1.2.c. Mutual fund

C: expected return of 16%, beta of 1.2.d. Mutual fund

D: expected return of 15%, beta of 0.9.