Watson Crick model of DNA was proposed on the basis of: (A) X-ray crystallography, (B) Chromatography, (C) Gel electrophoresis, (D) X-ray diffraction studies
Answer is A. (A) X-ray crystallography> X-ray crystallography theoretically offered the opportunity to reveal the molecular structure of large molecules like proteins and DNA, but there were serious technical problems then preventing X-ray crystallography from being applicable to such large molecules.