<prompt> Blood when stored at 4degC can be kept for ?7 days14 days21 days28 days  <response>: Ans. is c i.e., 21 days The recommend temperature for storage of blood is 1-6degC. Actually blood can be stored for more than 21 days, depending upon the type of additive used. Routine blood storage is limited to 21 days at 1-6degC when treated with acid-citrate-dextrose ACD or citratephosphate-dextrose CPD; and 35 days when treated with citrate-phosposphate-dextrose-adenine CPD-A; and 42 days when treated with saline-adenine-glucose-mannital SAG-M So, correct answer of this question can be: 21 days we have only this one in the options 35 days 42 days This is the best answer because SAG-M is the routinly used additive these days. Platelets are stored at 20-24degC for 3-5 days 