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: Physiology
[{'content': 'Toxic effects of high oxygen tension include all of the following, EXCEPT: \nSelect and explain. \nA. Pulmonary edema, B. Decreased cerebral blood flow, C. Retinal damage, D. CNS excitation and convulsion', 'role': 'user'}, {'content': "Answer: B \nExplanation: The High oxygen tension in inspired air produces cerebral vasoconstriction and reduces cerebral blood flow, thereby protecting the brain from the dangers of oxygen toxicity. Hence in this case, decreased cerebral blood flow is a protective mechanism and not a toxic effect of oxygen. Ref: Concise Medical Physiology By Chaudhuri, 5th Edition, Page 228; Goodman and Gilman's Manual of Pharmacology and Therapeutics, 11th Edition, Pages 393-94; Guyton and Hall Medical Physiology, 11th Edition, Page 547", 'role': 'assistant'}]