Multiple choice

Which blood group is called the "universal donor"?

  1. O+

  2. O-

  3. AB

  4. A

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

O-negative (O-) blood is known as the universal donor type because its red blood cells lack A, B, and Rh antigens, meaning it can be transfused to patients of any blood type without triggering an immune reaction.