单选题 Tom Wilkens is a portfolio manager and has a retiree as a client. The client would like to invest in bonds with low interest rate risk. Which bond should Tom choose for his client? The bond with a: A. 20 year maturity and a yield to maturity of 5%. B. 10 year maturity and a yield to maturity of 8%. C. 10 year maturity and a yield to maturity of 5%.