This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
Which of the following is the hallmark of programmed cell death? 
Select and explain. 
A. Apoptosis, B. Coagulation necrosis, C. Fibrinoid necrosis, D. Liquefaction necrosis
A: Apoptosis
Answer: A: Apoptosis 
Explanation: Apoptosis results from the activation of enzymes called caspases (so named because they are cysteine proteases that cleave proteins after aspaic residues). The activation of caspases depends on a finely tuned balance between production of pro- and anti-apoptotic proteins. Two distinct pathways converge on caspase activation: the mitochondrial pathway and the death receptor pathway.( Robbins Basic Pathology, 9th edition, page 19 )