This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.N.S, Subject name: Medicine
Muscles supplied by following nerve is affected least by myasthenia gravis 
Select and explain. 
A. III, B. IV, C. VI, D. None
D: None
Answer: D: None 
Explanation: The cranial muscles paicularly the lids and extraocular muscles are often involved early in the course of MG and diplopia and ptosis are common initial complaints. Ref Harrison20th edition pg 2786