19. Based on historical data, a reasonable estimate of the correlation between stocks and commodities is 0.10. The average annual return and standard deviation for stocks are 12% and 15%, respectively. The average annual return and standard deviation for commodities are 4% and 13%, respectively. Based on these numbers, the optimal portfolio contains 25% commodities and 75% stocks, which is a surprisingly large allocation to commodities. Which of the following is the key driver of this large allocation? A. Commodity returns' lower standard deviation makes them less risky B. The low correlation between stocks and commodities C. Commodities have a higher Sharpe Ratio than stocks. D. Commodities' higher average return