This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Head & Neck, Subject name: Anatomy
[{'content': 'Choose the appropriate lettered structure in this MRI scan showing a sagittal section through the head and neck. A lesion of the first cervical spinal nerve would cause functional impairment of which structure? \nSelect and explain. \nA. A, B. B, C. C, D. D', 'role': 'user'}, {'content': 'Answer: C \nExplanation: (c) The geniohyoid muscle is innervated by the first cervical nerve through the hypoglossal nerve.', 'role': 'assistant'}]