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 vertical axis is resisted by \nSelect and explain. \nA. Rigidity of major connector, B. Reciprocal clasp arms, C. Retentive clasp arms, D. All of the above', 'role': 'user'}, {'content': 'Answer: B \nExplanation: It is resisted by stabilizing components, such as reciprocal clasp arms and minor connectors that are in contact with vertical tooth surfaces. Such stabilizing components are essential to any partial denture design regardless of the manner of support and the type of direct retention employed. Stabilizing components on one side of the arch act to stabilize the partial denture against horizontal forces applied from the opposite side.', 'role': 'assistant'}]