Which of the Following Statements About Heparan Sulfate Is Not

Which of the following statements about heparan sulfate is not true?

A) Sulfation of heparan sulfate to form NS domains is important for its role as an anti-coagulant.
B) Heparan sulfate can promote protein-protein interactions via the NS domains.
C) The secondary structure of heparan sulfate is completely random.
D) The NA domains of heparan sulfate contain no sulfation.
E) The core repeating structure of heparan sulfate is made up of alternating GlcNAc and GlcA.