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
Which is NOT a feature of polymyositis -a) Ocular muscle involvementb) Gottron's rashc) Proximal muscle involvementd) Pain in limbs 
Select and explain. 
A. ac, B. ab, C. ad, D. bc
B: ab
Answer: B: ab 
Explanation: None