A Patient, Age 24, Had a Traumatic Amputation of His

A patient, age 24, had a traumatic amputation of his left foot in a motorcycle accident. He is receiving morphine by a patient-controlled analgesia (PCA) device. He complains of a burning sensation in his left foot. The nurse should explain that

A) this is a phantom pain and that its cause is not clearly understood.
B) this is not possible because his foot was amputated.
C) his regular pain medication will relieve the pain.
D) this phantom pain will disappear in about 1 week.