Debra is an investor just starting out in the stockmarket. She starts with a purchase of $10,000 of shares in ABC Ltd which has a standard deviation of returns of 10% p.a. She then invests another $10,000 purchasing shares in XYZ Ltd which has a standard deviation of returns of 40% p.a.. She estimates that the standard deviation of returns of their portfolio has increased from 10% p.a. before the XYZ purchase to 22% p.a. after the purchase. Which of the following statements correctly describe what has happened (or could have happened) to the risk position of Debra's portfolio following the investment in XYZ ? The maximum diversification benefit that Debra could expect is if the correlation coefficient between the returns of the two assets is equal to zero More than one of the other statements is correct Debra has not experienced any diversification benefit Debra would only achieve a diversification benefit if the correlation coefficient between the returns of ABC and XYZ shares is less than +1