challenge: What causes the eyelid to fall upon opening of the mouth in the Inverse Marcus Gunn phenomenon?
  
  A. Trigeminal innervation to the levator palpebrae superioris
  B. Stimulation of the oculomotor nerve to the pterygoid muscles
  C. Inhibition of the oculomotor nerve to the levator palpebrae superioris
  D. Stimulation of the trigeminal nerve to the levator palpebrae superioris
  Answer: 