A Patient Who Has Stable Angina and Uses Sublingual Nitroglycerin

A patient who has stable angina and uses sublingual nitroglycerin tablets is in the clinic and begins having chest pain.The primary care NP administers a nitroglycerin tablet and instructs the patient to lie down.The NP's next action should be to:

A) obtain an electrocardiogram.
B) administer oxygen at 2 L/minute.
C) give 325 mg of chewable aspirin.
D) call EMS.