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: Dental
[{'content': 'In assessment of skeletal age, based on cervical vertebrae, as seen in lateral cephalometric radiograph, stage 3 indicates: \nSelect and explain. \nA. More than one year beyond peak growth, B. No growth, C. Less than one year prior to peak growth, D. Peak growth still a year or so ahead', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Vertebral ages can be calculated from the image of the cervical vertebrae seen in a lateral cephalometric radiograph.\n\n(A) Diagrammatic drawings and relationships of the stages to the peak of mandibular growth.\n(B) Stage 2, indicating that peak growth at adolescence is still a year or so ahead.\n(C) Stage 3, which on average occurs less than 1 year prior to peak growth.\n(D) Stage 4, typically a year or so beyond peak growth.\n(E) Stage 5, more than 1 year beyond the peak of the growth spurt, probably with more vertical than anteroposterior growth remaining.\n(F) Stage 6, more than 2 years beyond peak growth (but\xa0a patient with a severe skeletal problem, especially excessive mandibular growth, is not necessarily ready for\xa0surgery;\xa0the\xa0best\xa0way\xa0to\xa0determine\xa0the\xa0cessation\xa0of\xa0growth\xa0is\xa0serial\xa0cephalometric\xa0radiographs).', 'role': 'assistant'}]