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: Anatomy
[{'content': 'The posterior bellies of digastric muscle are especially active during \nSelect and explain. \nA. Swallowing and speech, B. Swallowing and smiling, C. Swallowing and chewing, D. Swallowing and frowning', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Digastric\n\nOrigin – The posterior bellay arises from the mastoid, or digastric, notch immediately behind the mastoid process of the temporal bone.\nInsertion – The posterior belly passes downwards and forwards towards the hyoid bone where it becomes the intermediate digastric tendon and joints with the anterior belly.\nNerve\xa0supply – Derived from the digastric branch of the facial nerve.\nVasculature – Arterial blood supply from the posterior auricular and occipital arteries.\nAction – The muscle depresses the mandible and can elevate the hyoid bone. The posterior bellies act in unison and are particularly active during swallowing and chewing.', 'role': 'assistant'}]