The patient who experiences loss of taste, dry mouth, and inability to close the eye has Bell’s Palsy which is due to a viral infection. In Bell’s Palsy, the cranial nerve affected by the viral infection is the facial (VII) nerve its axons extend from the taste buds of the anterior portion of the tongue and enter the temporal bone where it joins the facial nerve (Tortora & Derrikson, 2012).
Reference:
Tortora, & Derrickson. (2012). Chapter 14: The Brain and Cranial Nerves. In Principles of anatomy and physiology (13th ed.). Pp. 564.