While Caring for a Patient with Respiratory Disease, the Nurse

While caring for a patient with respiratory disease, the nurse observes that the patient's SpO₂ drops from 94% to 85% when the patient ambulates in the hall. The nurse determines that

A) supplemental oxygen should be used whenever the patient exercises.
B) arterial blood gas analysis should be done to verify the patient's SpO₂.
C) the response is normal and the patient should continue at this activity level.
D) the patient activity should be limited until the disease process is resolved.