Duration Matching Strategy for Liabilities

A fixed-income portfolio manager is tasked with developing a strategy to align his portfolio with upcoming liabilities that are expected to be fully paid in five years. He aims to minimize the interest rate risk associated with these liabilities. The manager has identified a set of bonds and their characteristics and is considering using a duration matching strategy to achieve this goal.

Which of the following actions should the portfolio manager take to effectively match the duration of his bond portfolio with the timing of the liabilities?