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: Unknown
[{'content': 'All are platelet aggregators except: \nSelect and explain. \nA. ADP, B. Thromboxane, C. Steroids, D. PGD2', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans- D PGD2 Ref: Robbins Pathologic Basis of Disease, 8th edition, Pg: 589 Explanation: Platelet aggregation stimulators ADP. Thromboxane, and a 2 receptor-activation, but Exogenous anabolic steroids Platelet aggregation inhibitors PGI2 PGD2.', 'role': 'assistant'}]