8. In sickle cell hemoglobin, a Glu is mutated to a _____ . This causes the formation of _____ between hemoglobinmolecules, ultimately forming large aggregates.
(A)Arg； salt bridges
(B) Cys； disulfide bonds
(C) Val； hydrophobic interactions
(D) Pro； disrupted o-helix, resulting in several H-bonds and salt bridges
(E) None of the above