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: Biochemistry
[{'content': 'Which of the following is not a free radical, but it is a reactive oxygen species? \nSelect and explain. \nA. Hydroxyradical, B. Hydrogen peroxide, C. Superoxide radical, D. Both 1 & 2', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Most powerful oxygen free radical is Hydroxyradical.\nLeast powerful Reactive Oxygen species(ROS) is Hydrogen peroxide.\nPrecursor of all Reactive Oxygen species is Superoxide radical.\nH2O2 is not a free radical,\xa0 but a ROS.\n\nReference- Review of biochemistry Pg-411', 'role': 'assistant'}]