This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Brain , Subject name: Anatomy
Nucleus ambiguous doesn&;t include 
Select and explain. 
A. 7th nerve nucleus, B. 9th nerve nucleus, C. 10th nerve nucleus, D. 11th nerve nucleus
A: 7th nerve nucleus
Answer: A: 7th nerve nucleus 
Explanation: The nuclei of facial nerve are located in the pons.Nucleus ambiguous is an elongated column of typical motor neurons extending throughout the medulla.The fibres from nucleus ambiguous supplies muscles derived from 3,4 and 6 branchial arches. Cells in nucleus ambiguous contain motor neurons associated with three cranial nerves (rostral pole -C.N. IX glossopharyngeal; middle pa -C.N. X vagus; caudal pole -C.N. XI spine accessory).(Ref: Vishram Singh textbook of clinical neuroanatomy second edition pg 94)