The pH of blood does not appreciably change by a small addition of acid or a base because blood
A.contains serum protein which acts as buffer✓ Correct
B.contains iron as a part of the molecule
C.can be easily coagulated
D.is body fluid.
Explanation
Our blood consists of serum which is a protein. The buffer system present in blood is 2 3 3 H CO NaHCO . A buffer solution resists the change occurred in pH. Therefore, pH value of blood does not change by a small addition of any acid or a base.