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 forces that hold atoms together are called \nSelect and explain. \nA. Primary forces, B. Secondary forces, C. Cohesive forces, D. Ionic forces', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]