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': 'The finger rest established on tooth surfaces on the opposite side of the same arch is known as: \nSelect and explain. \nA. Conventional finger rest, B. Opposite arch finger rest, C. Cross - arch finger rest, D. Finger - on - finger rest', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]