This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cellular Pathology, Subject name: Pathology
In apoptosis, cytochrome C acts through: 
Select and explain. 
A. Apaf 1, B. Bcl-2, C. FADD, D. TNF
A: Apaf 1
Answer: A: Apaf 1 
Explanation: Ans. (a) Apaf 1(Ref Robbins 9th/pg 54-55; 8th/pg 29)Leakage of cytochrome c, other proteins form the inner mitochondrial membrane to cytosol|Cytochrome C binds to APAF-1Q|Activation of caspase-9-critical initiator caspase of the mitochondrial pathway