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: Pediatrics
Platelet function is assessed by: 
Select and explain. 
A. Platelet adhesion, B. BT, C. PFA-100, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Platelet function assessment: - PFA-100--This is a test to measure the platelet adhesion-aggregation in response to agonist combination like collagen epinephrine or collagen-ADP. - Bleeding time--The usual bleeding time is 4-8 minutes. Bleeding for a longer time suggests platelet defects.