The nurse teaches a patient to self-administer his insulin. How can the nurse best evaluate whether the patient understands the instruction?

A. Ask the patient an open-ended question about feelings: This might reveal anxieties but not necessarily confirm understanding of the steps. B. Ask the patient to repeat the information in the pamphlet: Repeating information doesn't guarantee comprehension of how to perform the task. C. Have the patient list the steps: This can be helpful, but observing actual performance allows for correcting any errors in technique. D. Observe as the patient prepares and injects a dose of insulin: Direct observation is the most reliable way to assess if the patient can safely and accurately self-administer insulin.