In bacteria, N-formyl methionine is the first amino acid to be incorporated into a polypeptide chain. Accordingly, one would think that all bacterial proteins have a formyl group at their amino acid terminals, and the first amino acid is methionine. however, this is not the case because of the following possible reasons:

A. Deformylase removes the formyl group only during or after the synthesis of polypeptides 

B. Aminopeptidase removals only the amino-terminal methionine.

C. Aminopeptidase removes  the Amino-terminal As well as one or two additional amino acids

D. Deformylase removes the formal group as well as amino terminal methionine And arts one or two amino acids to it

 choose the correct combination from the following