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': 'Highest bond strength is found in which generation of dentin bonding agent? \nSelect and explain. \nA. 4th generation, B. 5th generation, C. 6th generation, D. 7th generation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Bonding strength of dentin bonding agents generations:\n\nFirst -\xa0 2-3 MPa\nSecond – 1-5 MPa\nThird – 3-13 MPa\nFourth – 13-80 MPa\nFifth – 3-75 Mpa\xa0\nSixth – 10-75 Mpa\xa0\nSeventh – 0-60 Mpa', 'role': 'assistant'}]