This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
Primary idiopathic polymyositis does not involve - 
Select and explain. 
A. Pelvic girdle muscles, B. Neck muscles, C. Ocular muscles, D. Pharyngeal muscles
C: Ocular muscles
Answer: C: Ocular muscles 
Explanation: None