This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cranial Nerves, Subject name: Anatomy
Which of the following reflexes test the integrity of nucleus ambiguus 
Select and explain. 
A. Jaw jerk, B. Stapedial reflex, C. Gag reflex, D. Corneal reflex
C: Gag reflex
Answer: C: Gag reflex 
Explanation: Nucleus ambiguus involves cranial nerves 9th, 10th & 11th . It involves the nerve supply to soft palate , larynx & pharynx which is involved in speech & swallowing. Gag reflex: Contraction of the constrictor muscle of the pharynx elicited by touching the back of the pharynx.