Answer the following question given this paragraph: 

The ABO blood group system is important if a person needs a blood transfusion. A blood transfusion is the process of putting blood or blood products from one person into the circulatory system of another person. The blood type of the recipient needs to be carefully matched to the blood type of the donor. That's because different blood types have different types of antibodies, or proteins, released by the blood cells. Antibodies attack strange substances in the body. This is a normal part of your immune response, which is your defense against disease.


Q: Matching donor and recipient blood types is important because different blood types have different types of what?

 Choices:

- antigens

- charges

- coagulants

- antibodies

A:
antibodies
