Which of the following descriptions about tertiary structure of protein are correct

A、All polypeptide chains with tertiary structure have biological activities.;

B、Most hydrophilic groups are located on the surface of tertiary structure.;

C、The stability of tertiary structure is maintained by covalent bonds.;

D、Tertiary structure is three-dimensional arrangement of all atoms in a polypeptide chain.;

E、Formation of tertiary structure is the result of interaction between side chain groups of a polypeptide chain.