Which of the following is a wrong statement?

• A. To assume biological activity, many nascent polypeptides have to be covalently modified before or after the folding process
• B. In eukaryotic cells most modifications take place in the endoplasmic reticulum and the Golgi apparatus
• C. The modifications in eukaryotic cells include proteolytic cleavage; formation of disulfide bonds; addition of phosphoryl, methyl, acetyl, or other groups onto certain amino acid residues
• D. The modifications in eukaryotic cells doesn’t include attachment of oligosaccharides or prosthetic groups to create mature proteins