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': 'Grain elongation is due to \nSelect and explain. \nA. Cold working, B. Recrystallisation, C. Recovery, D. Age hardening', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The average grain size of the recrystallized structure depends on the initial number of nuclei. The more severe the degree of cold working, the greater is the number of such nuclei. The grain size for the recrystallized metal can range from rather relatively fine to fairly coarse.\nPhillips 12th edition page no 405', 'role': 'assistant'}]