In evaluating the effectiveness of a postoperative client's intermittent pneumatic compression devices, which assessment is most important for the nurse to complete?

A. Monitoring incision drainage is important for infection and wound healing but not directly related to the effectiveness of compression devices. B. Observing both lower extremities for redness and swelling directly assesses the effectiveness of the pneumatic compression devices in preventing deep vein thrombosis (DVT). C. Evaluating the use of an incentive spirometer is important for respiratory function but unrelated to the compression devices. D. Palpating peripheral pulse points is useful for circulation assessment but does not specifically evaluate the prevention of DVT, which is the primary purpose of the compression devices.