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: ENT
Trismus in parapharyngeal abscess is due to spasm of: 
Select and explain. 
A. Masseter muscle, B. Medial pterygoid, C. Lateral pterygoid, D. Temporalis
B: Medial pterygoid
Answer: B: Medial pterygoid 
Explanation: Styloid process divides the pharynx into anterior and posterior compament. Trismus occurs in infection of anterior compament whereas toicollis (due to spasm of paraveebral muscles) occurs in the infection of posterior compament.