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': 'Rotation of a distal extension base around longitudinal axis is resisted by \nSelect and explain. \nA. Rigidity of major connector, B. Rigidity of minor connector, C. Both of the above, D. None of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: A second movement is rotation about a longitudinal axis as the distal extension base moves in a rotary direction about the residual ridge. This movement is resisted primarily by the rigidity of the major and minor connectors and their ability to resist torque.', 'role': 'assistant'}]