7. Which of the following proteins moves toward the anode the fastest during electrophoresis at a pH of 7.0? (A) protein A (molecular weight 25kDa, isoelectric point 7.0) (B) protein B (molecular weight 200kDa, isoelectric point 4.5) (C) protein C (molecular weight 25kDa, isoelectric point 4.5) (D) protein D (molecular weight 25kDa, isoelectric point 9.5) (E) protein E (molecular weight 200kDa, isoelectric point 9.5)