This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous System, Subject name: Physiology
[{'content': 'Root value of biceps jerk? \nSelect and explain. \nA. C5C6, B. C4C5, C. C6C7, D. c8T1', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. a (C5 C6). (Ref. Ganong, Physiology, 21st/pg. l30)SPINAL LEVELREFLEXC5-6SupinatorC5-6BicepsC7TricepsL3-4KneeS1AnkleEducational points:Spinal Cord Levels Relative to the Vertebral BodiesSpinal Cord LevelCorresponding Vertebral BodyUpper cervicalSame as cord levelLower cervical1 level higherUpper thoracic2 levels higherLower thoracic2 to 3 levels higherLumbarT10-T12SacralT12-L1', 'role': 'assistant'}]