42. A portfolio that belongs to the Markowitz efficient set of portfolios will have which one of the following characteristics? Assume the portfolios are comprised of ve individual securities. A. the lowest return for any given level of risk B. the largest number of potential portfolios that can achieve a specific rate of return C. the largest number of potential portfolios that can achieve a specific level of risk D. a positive rate of return and a zero standard deviation E. the lowest risk for anv given rate of return