Carbonic anhydrase activity found in all except

Carbonic anhydrase activity found in all
except?
a) Brain
b) Kidney
c) RBC
d) Plasma
Correct Answer - D
Ans.D . Plasma
Carbonic anhydrase (CAse) is an enzyme which catalyzes the
reversible reaction of formation of bicarbonate ions,
The enzyme is present in renal tubular cells (especially PT), gastric
mucosa, exocrine pancreas, ciliary body of eye, brain and RBC.