challenge: What may be a consequence of damage to the frontonasal duct due to frontal bone fractures?
  
  A. Impaired drainage of the frontal sinus and predisposition to intracranial spread of infection
  B. Reduced risk of sinusitis
  C. Increased risk of mucocele formation in the maxillary sinus
  D. Improved drainage of the frontal sinus
  Answer: 