This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Anatomy
[{'content': 'Nuclear bag fibre detects \nSelect and explain. \nA. Sense dynamic length of muscle, B. Involved in reciprocal innervations, C. Alpha motor neuron stimulation, D. Senses muscle tension', 'role': 'user'}, {'content': "Answer: A \nExplanation: (Refer Q 5 AIIMS Nov'14)", 'role': 'assistant'}]