单选题 An investor has a $15000 portfolio consisting of $10000 in stock A with an expected return of 20 percent and $ 5000 in stock B with an expected return of 10 percent. What is the investor's expected return on the portfolio?

A.7.9%.
B. 12.2%.
C. 16.7%.

【正确答案】 C

【答案解析】Find the weighted mean where the weights equal the proportion of $15000. [(10000/15000)×0.20]+[(5000/15000)×0.10]=16.7%.