Rosalind franklin used x-ray diffraction to determine dna structure. Her data were used by james watson and francis crick to determine the structure of dna. What did her data suggest about the structure of dna?

a. the amount of a is equal to the amount of t and the amount of c is equal to the amount of g.
b. adenine forms hydrogen bonds with thymine and guanine forms hydrogen bonds with cytosine.
c. dna forms a helical structure and has a uniform diameter of about 20 angstroms.
d. dna is a single linear strand.