13. Which one of the following statements is correct? A) Marketable securities are generally low-risk, high-return investments. B) The rate of return earned on short-term securities tends to exceed that earned on long-term securities. C) U.S. Treasury bills are highly liquid in terms of secondary market liquidity. D) The income earned on U.S. Treasury bills is exempt from all taxation. E) Short-term investments tend to have high levels of default risk