This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Blood, Subject name: Pathology
Storage period of 35 days for blood is seen with: 
Select and explain. 
A. Citrate-phosphate-dextrose (CPD), B. Citrate-phosphate-dextrose-alanine-1 (CPDA-1), C. Acid-citrate-dextrose (ACD), D. Citrate-phosphate-dextrose-dextrose (CP2D)
B: Citrate-phosphate-dextrose-alanine-1 (CPDA-1)
Answer: B: Citrate-phosphate-dextrose-alanine-1 (CPDA-1) 
Explanation: ANS. B# Storage period and preservatives* CPD--21 days* ACD--21 days* CPDA--35 days* SAGM--42 daysSAGM: Saline, adenine, glucose, mannitolFunction of SAGM: Increases shelf life of red blood cell (RBC)CPD:* Citrate--Ca2+ chelator* Phosphate--increased 2, 3, DPG and buffering* Dextrose--nutrition.