An investor can design a risky portfolio based on two stocks, A and B. The standard deviation of return on stock A is 20%, while the standard deviation on stock B is 15%. The correlation coefficient between the returns on A and B is 0%. The rate of return for stocks A and B is 20% and 10% respectively. The expected return on the minimum-variance portfolio is approximately ________. A. 19.41% B. 13.6% C. 15% D. 10%