This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bleeding Disorders, Subject name: Pathology
In PT test, the addition of Ca2+ & tissue thromboplastin activates which pathway? 
Select and explain. 
A. Extrinsic, B. Intrinsic, C. Fibrinolytic, D. Common
A: Extrinsic
Answer: A: Extrinsic 
Explanation: Ans. (a) ExtrinsicTo PT we add of Ca2+ & tissue thromboplastin which activates extrinsic pathway, while to test for aPTT we add kaolin, silica which activates intrinsic pathway.