Which of th DNA profiling

B. Gene mapping

C. DNA finger printing

D. X-ray diffraction

X-ray diffraction is an old technique which was used to determine the structure of a compound. Structure of DNA was also determined by this technique initially.

All other techniques DNA profiling, Gene mapping and DNA finger printing are modern genetic engineering techniques which help us to determine the complete genome of any organism along with the locations of all genes.

Therefore, correct answer is (d) X- ray diffraction.