How Does Blood Doping Work

How does blood doping work?

A) White blood cells are extracted, stored, and reinjected prior to competition to enhance oxygen uptake and endurance.
B) Red blood cells are extracted, stored, and reinjected prior to competition to enhance oxygen uptake and endurance.
C) Drugs are injected prior to competition, which enhance oxygen uptake and endurance.
D) Drugs are injected prior to competition, which enhance muscle strength and minimize pain sensation.
E) Prior to competition, a blood transfusion occurs in order to increase overall blood volume to enhance endurance.