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': 'Water tree phenomenon is seen in \nSelect and explain. \nA. Generation 1 DBA, B. Generation 4 DBA, C. Generation 6 DBA, D. Generation 7 DBA', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Water tree phenomenon is microscopic appearance in cured layer of dentin adhesive due to incomplete water evaporation. Seen in 7th\xa0generation Dentin Bonding Agent.', 'role': 'assistant'}]