A nurse is reinforcing teaching with a client who has a prescription for sildenafil to treat erectile dysfunction. Which of the following statements by the client indicates an understanding of the teaching?

B. Fatty foods can delay the absorption of sildenafil, potentially delaying its onset of action. While it's not necessary to completely avoid fatty foods, consuming a high-fat meal shortly before taking sildenafil may delay its effects. Therefore, it's advisable to avoid large, high-fat meals before taking sildenafil to optimize its effectiveness. A. Sildenafil is typically taken on an as-needed basis, approximately 30 minutes to 1 hour before anticipated sexual activity. Taking sildenafil more than once a day is not recommended and can increase the risk of adverse effects and complications. C. Sildenafil is a medication used to treat erectile dysfunction by improving blood flow to the penis, but it does not protect against sexually transmitted diseases (STDs). D. Constipation is not a common side effect of sildenafil. Common side effects of sildenafil include headache, flushing, indigestion, nasal congestion, and dizziness. Constipation is not typically associated with sildenafil use.