Identify the incorrect statement about the tertiary structure of proteins.

• A
  They can be fibrous or globular in structure.
• B
  The main forces that stabilize the structure are hydrogen bonding, disulphide links, van der Waals and electrostatic forces of attraction.
• C
  The structure remains intact when exposed to pH changes.
• D
  $A$ linear polypeptide chain will convert to a secondary structure and then further folding of the secondary structure will convert to tertiary structure.