If blood is in short supply, which blood type would be the most beneficial to have on hand if someone needed a blood transfusion?

O– red blood cells can be transfused to people of any ABO and Rh blood type, so they are especially useful when the recipient’s blood type is unknown or supplies are limited. The other choices can only be safely given to a narrower range of recipients. Therefore, O– is the most beneficial type to have on hand.

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