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': 'During the development of a tooth, sound coalescence of the lobes results in \nSelect and explain. \nA. Grooves, B. Fissures, C. Cusps, D. All of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]