Janet is retired with a fixed income portfolio and requires this investment income to support her needs. While meeting with Pierre, a CFP professional, she comments that interest rates have fallen significantly over the past decade. She recalls a considerable drop in income when she reinvested funds in a low interest rate environment. To address this concern, which of the following strategies would be most appropriate for Pierre to recommend? As the bonds mature, invest in a portfolio of: a) treasury bills. b) bonds with short-term maturities. c) bonds with laddered maturities. d) bonds with long-term maturities.