Question 3 4 pts Which of the following statements is true? a. Beta is the slope of the security market line. b. A stock with a beta of 1.00 has a required return equal to the required return on the market. c. Adding a stock with a high standard deviation to a portfolio always increases the risk of the portfolio d. The higher is a stock's beta, the lower is the standard deviation of the stock's returns. e. both b and d are correct