This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Pathology
[{'content': '. The pH of the freshly collected blood in CPD solution bag is - \nSelect and explain. \nA. 7*1, B. 7*3, C. 7*4, D. 7*6', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Answer is option 3,ph7.4 donation of whole blood is most commonly collected in acidic citrate-phosphate-dextrose (CPD) variants with pH 5.2 to 6.2 as anticoagulants. Previously, we have shown that the initial pH after red blood cell (RBC) preparation can have an effect on RBCs during storage. First, we investigated the effect of the pH of the anticoagulant on RBCs. Second, we investigated the possibility of decreasing the pH of our new additive solution (AS) phosphate-adenine-glucose-guanosine-gluconate-mannitol (PAGGGM) from pH 8.2 to 7.4 in combination with an anticoagulant with a physiologic pH. Ref baley and love edition number 27.pg 15-17', 'role': 'assistant'}]