An elderly client is brought to the emergency department with lethargy, chills, and sharp chest pain with deep breathing. Pulse oximeter shows 93% on room air and respirations are 24/min. What is the nurse's initial action?
a. Administer intravenous (IV) morphine
b. Auscultate the client's lung sounds
c. Initiate an IV infusion of normal saline
d. Initiate nasal oxygen at 3 L/min