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': 'Intrusion is best produced by \nSelect and explain. \nA. Light intermittent forces, B. Heavy intermittent forces, C. Light continuous forces, D. Heavy continuous forces', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]