During an Examination,the Nurse Notes Severe Nystagmus in Both of the Patient's

During an examination,the nurse notes severe nystagmus in both of the patient's eyes.Which of the following conclusions is correct?

A) This is a normal occurrence.
B) This may indicate disease of the cerebellum or brain stem.
C) This is a sign that the patient is nervous about the examination.
D) This indicates a visual problem and a referral to an ophthalmologist is indicated.