This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Head and neck, Subject name: Anatomy
[{'content': 'Which of the following is the action of the lateral pterygoid muscle on the temporomandibular joint? \nSelect and explain. \nA. Elevation, B. Depression, C. Adduction, D. Abduction', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Depression of the mandible or opening of the mouth is produced mainly by the lateral pterygoid helped by gravity.Elevation is produced by the medial pterygoid, temporalis and masseter.Reference: Textbook of anatomy, Head Neck, and Brain, Vishram Singh, 2nd edition, page no.148', 'role': 'assistant'}]