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: Pathology
Which of the following are apoptosis assays? 
Select and explain. 
A. Annexin V assay, B. TUNEL technique, C. Transglutaminase activity, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: All the 3 are assays for apoptosis. Other assays include ISNT, FRET etc.
ISNT - In Situ Nick Translation
FRET - Fluorescence Resonance Energy Transfer