16. The double helix of DNA in the B-form is stabilized mostly by: (A) hydrogen bonds between the riboses of each strand. (B) ribose interactions with the planar base pairs. (C) nonspecific base-stacking interaction between two adjacent bases in the same strand. (D) hydrogen bonding between the phosphate groups of two side-by-side strands. (E) covalent bonds between the 3' end of one strand and the 5' end of the other.