A nurse is caring for a client who is postoperative following a total knee replacement. Which of the following actions should the nurse implement to prevent deep vein thrombophlebitis?

A. Increased fluid intake helps prevent hemoconcentration, thereby reducing the risk of clot formation and promoting circulation. B. Massaging the calf is contraindicated because it can dislodge a thrombus and cause a pulmonary embolism. C. Keeping the knee flexed impairs venous return and increases the risk for clot formation. D. Prolonged bed rest increases venous stasis and the risk of DVT; early ambulation is preferred.