Ans. A.A person with below normal platelet count can donateExplanationSpecific Eligibility Criteria for Apheresis Platelet DonorsAge: 18-60 years and Weight- 50 kg (This is not just for platelet donation but also for all blood and blood product donations in India)Donor platelet count must be > 1,50,000/dL (Option a)If taking anti-platelet medication:Aspirin- defer for at least 2 full medication-free daysClopidogrel or ticlopidine - defer for at least 14 full medication-free daysFrequency of donations:Can donate up to 2 times in a week (Option c)24 times in a year (Option d)Minimum interval between donationsMinimum of a 48 hour-interval needed after donating single unit (Option b)7 days after donating double or triple units.Other important points about platelet transfusionThreshold for prophylactic platelet transfusion is 10,000/mL.In patients without fever or infections, a threshold of 5000/mL may be sufficient to prevent spontaneous hemorrhage.For invasive procedures, the usual target level is 50,000/mL platelets.Platelets are produced in two ways:Random donor (RD) platelets: Whole blood donations are centrifuged and the buffy coats (between the red cell and plasma layers) from four donations are pooled in the plasma of one of the donors.Single donor apheresis platelets (SDAP): Platelets are obtained from a single donor by apheresis. SDAP contain the equivalent of at least 6 units of RD platelets and have fewer contaminating leukocytes than pooled RD platelets.Time required in collecting SDAP is 2 to 3 hours (in RD its 30 mins).Storage--20-24degC with agitationShelf life--5 days (7 days if bacterial screening)