When a Patient Has a Suspected Vestibular Disorder, the Physician

When a patient has a suspected vestibular disorder, the physician orders an electronystagmography test.Which instruction should the nurse include when educating the patient about this test?

A) Use tea or coffee on the morning of test.
B) Electrodes will be placed on the scalp.
C) Air will be blown into the external ear.
D) The patient should have nothing to eat or drink (NPO) 3 hours before the test.