Final answer:
James Watson and Francis Crick discovered the structure of DNA, using X-ray diffraction data from Rosalind Franklin.
Step-by-step explanation:
James Watson and Francis Crick are given most of the credit for discovering the structure of DNA. In the 1950s, Watson and Crick worked together at the University of Cambridge, England to determine the double helix structure of DNA. They used X-ray diffraction data from Rosalind Franklin to piece together the puzzle of DNA's structure. In 1962, Watson, Crick, and Maurice Wilkins were awarded the Nobel Prize in Medicine for their groundbreaking work.