Which statement about blood types is false?

A. Blood can be mixed safely.

B. There are four types of blood.

C. All blood types are compatible.

D. Blood types are classified by the type of red blood cells they contain.

c

Explanation

Answer c is wrong because the wrong blood type can cause threatening implications. The only blood type that can be considered compatible is blood type o. That is because it is known to be the universal donor.