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': 'Extrinsic pathway of coagulation is tested by? \nSelect and explain. \nA. PT, B. CT, C. aPTT, D. BT', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Simple tricks to remember questions of hemostasis:\n\nIntrinsic pathway – XII —> \xa0XI —> \xa0IX —> \xa0X (Help of VIII, IV)\nExtrinsic pathway – III —> VII —> X\nCommon pathway – X —> II —> I —> \xa0fibrin plug (help of V, XIII)\nVitamin K dependent clotting factors - 2, 7, 9, 10 (protein C and S) - mainly extrinsic pathway\nVitamin K antagonists - Coumarin derivatives (dicoumarol) and warfarin', 'role': 'assistant'}]