The nurse is preparing to administer the prescribed dose of nadolol to a client diagnosed with hypertension. What action should the nurse I take immediately before administering the dose?

A. Obtain a finger-stick glucose level: Nadolol is a nonselective beta-blocker that can mask signs of hypoglycemia, but routine glucose checks are not required immediately before each dose unless the client has diabetes or symptoms of low blood sugar. B. Measure and document a set of vital signs: Nadolol lowers heart rate and blood pressure by blocking beta-adrenergic receptors. Assessing apical pulse and blood pressure immediately before administration ensures the medication is safe to give and helps prevent bradycardia or hypotension. C. Draw blood for renal function laboratory tests: Nadolol is excreted renally, so kidney function is monitored over time rather than immediately before each dose. This assessment does not directly determine whether the dose should be administered at that moment. D. Request a 12-lead electrocardiogram: A routine ECG is not required before administering nadolol unless the client has new cardiac symptoms or known conduction abnormalities. Heart rate and blood pressure assessment provide the most immediate and relevant safety information.