The Nurse Notes New Onset Confusion in an Older Patient

The nurse notes new onset confusion in an older patient who is normally alert and oriented.In which order should the nurse take the following actions? (Put a comma and a space between each answer choice [A,B,C,D].)
A) Obtain the oxygen saturation.
B) Check the patient's pulse rate.
C) Document the change in status.
D) Notify the health care provider.