Answer :
Final answer:
Facial nerve palsy is identified by the nurse as the defect caused by difficult forceps delivery, characterized by weakness in the facial muscles on one side. Hence the correct option would be option b.
Explanation:
The nurse recognizes that the injury sustained by the infant with facial paralysis related to the use of forceps is a form of facial nerve palsy. Facial nerve palsy is characterized by muscle weakness that causes one half of the face to droop, known as Bell's Palsy, when the cause is idiopathic, though birth trauma is also a known risk factor. The use of forceps during delivery can exert pressure on the facial nerve, leading to this temporary or sometimes permanent damage. Facial nerve palsy differs from cranial nerve injury, facial bone fracture, and facial muscle weakness in the context of the underlying cause and presentation.