Answer : 2. "James Watson and Francis Crick"
Explanation :

Answer: B) James Watson and Francis Crick Explanation: In the early 1950s two scientists, Rosalind Franklin and Maurice Wilkins, studied DNA using x-rays. Franklin produced an x-ray photograph that allowed two other researchers, James Watson and Francis Crick to work out the 3D structure of DNA. The structure of DNA was found to be a double helix.