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: Pathology
The following site is commonly involved in cases of Myositis ossiﬁcans: 
Select and explain. 
A. Masseter, B. Hyoglossus, C. Stylohyoid, D. Lateral pterygoid
A: Masseter
Answer: A: Masseter 
Explanation: Myositis ossiﬁcans manifests by masses of ﬁbrous tissue and bone in the interstitial tissues of muscle, leading to atrophy and destruction of associated muscles. Masseter is commonly involved in face and ﬁxation of jaw occurs. The patient becomes transformed into rigid, like a "petriﬁed man'.