7) If an investor does not diversify his portfolio and instead puts all of his money in one stock, the appropriate measure of security risk for that investor is the __ A) covariance with the market index B) stock's beta C) variance of the market D) stock's standard deviation 8) Decreasing the number of stocks in a portfolio from 50 to 10 would likely A) increase the systematic risk of the portfolio B) increase the return of the portfolio C) increase the unsystematic risk of the portfolio D) decrease the variation in returns the investor faces in any one year