This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Apoptosis, Subject name: Pathology
Apoptosis is initiated by? 
Select and explain. 
A. Caspases, B. Bd-2, C. Bd-X, D. P53
A: Caspases
Answer: A: Caspases 
Explanation: ANSWER: (A) CaspasesREF: Robbins 8th Edn Page 295-296See Mechanism of Apoptosis in Pathology 2013 Session 1