This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pancreas, Subject name: Surgery
Most Commonly done screening test for diagnosing Acute Pancreatitis 
Select and explain. 
A. Serum amylase, B. Serum lipase, C. Serum trypsin, D. NBT PABA
A: Serum amylase
Answer: A: Serum amylase 
Explanation: Ans. (a) Serum AmylaseRef: Bailey and Love 27th ed. pg. 1214* Most common used to diagnose Acute pancreatitis - Serum amylase (will be elevated for first 3 days and declines in 4-8 days)* Serum Lipase though more sensitive is not widely available.