A nurse is reinforcing teaching with a client who has a new prescription for sustained-release verapamil. Which of the following statements by the client indicates an understanding of the teaching?

A. "I will crush the tablet to make it easier to swallow.": Sustained-release tablets should not be crushed or chewed, as this alters the release mechanism. B. "I will increase my daily intake of fiber and fluid.": Verapamil can cause constipation, so increasing fiber and fluid intake helps prevent this side effect. C. "I will follow up with monthly laboratory tests to check for anemia.": Verapamil does not typically require monitoring for anemia. D. "I will sit upright for 30 minutes after taking the medication.": This advice is more relevant for medications that can cause esophageal irritation, such as bisphosphonates, not verapamil.