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': 'Best way to join cast titanium components \nSelect and explain. \nA. Laser Welding, B. Oven Soldering, C. Torch Soldering, D. Infrared Soldering', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Laser welding in an argon gas atmosphere is a method of choice for joining titanium components of dental prostheses, because the coherent, high-intensity laser pulse of light can be focused in a small region and melt the substrate without extensive microstructural damage to the surrounding areas. An advantage of welding is that the joint will be composed of the same pure titanium as the substrate components, thereby preserving the excellent biocompatibility potential of CP Ti.\xa0\nPhillip’s 12th edition page 392', 'role': 'assistant'}]