A 45-year-old patient who is alert and oriented has a blood pressure of 98/66 mm Hg, radial pulse of 76 beats/min (irregular), and respirations of 18 breaths/min (regular). The best nursing intervention is to:
a) Administer a vasopressor medication
b) Encourage deep breathing exercises
c) Monitor the patient closely
d) Initiate cardiopulmonary resuscitation (CPR)