Multiple choice

The classification of human blood into A, B and O types was done by ______.

  1. Harvey

  2. Ringer

  3. Landsteiner

  4. Pasteur

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

Karl Landsteiner discovered the ABO blood group system in 1901, for which he received the Nobel Prize. Harvey discovered blood circulation, Ringer developed Ringer's solution, and Pasteur contributed to germ theory. Landsteiner's work on blood antigen-antibody reactions revolutionized transfusion medicine.