24. To determine the isoelectric point of a protein, first establish that a gel:
(A) contains a denaturing detergent that can distribute uniform negative charges over the protein'ssurface.
(B) exhibits a stable pH gradient when ampholytes become distributed in an electric field.
(C) is washed with an antibody specific to the protein of interest.
(D) neutralizes all ionic groups on a protein by titrating them with strong bases.
(E) relates the unknown protein to a series of protein markers with known molecular weights, Mr.