The Patient Has Been in the Hospital for Several Days

The patient has been in the hospital for several days for urosepsis.He has been responding favorably to treatment,and his vital signs have been "normal" for 2 days.When the nurse takes his vital signs,however,the patient's apical pulse is 152 and regular.The nurse suspects that the:

A) patient is having a reaction to his narcotic medication.
B) patient may be suffering from hypothermia.
C) patient's fever may have returned.
D) patient may be an athlete.