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': 'Cohesion of gold foil is an example of: \nSelect and explain. \nA. Atomic attraction and welding, B. Annealing, C. Wedging, D. Adaptation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Pure gold is the noblest of all dental metals, rarely tarnishing or corroding in the oral cavity. It is inactive chemically, and it is not affected by air, heat, moisture, or most solvents. At room temperature, two thin sheets of atomically clean pure gold can be welded under\xa0 pressure. The\xa0 procedure\xa0 is\xa0 also called cold welding because it is conducted at room temperature.\nRef: Phillips 12 ed page no 413', 'role': 'assistant'}]