Answer: Watson and Crick used a combination of X-ray crystallography data from Rosalind Franklin and Maurice Wilkins, along with model building and hypothesis testing, to solve the structure of DNA.
Step-by-step explanation:
Rosalind Franklin's X-ray diffraction images of DNA provided crucial data about the helical nature of DNA fibers. Using this data, along with their own model building and experimental data from other researchers, James Watson and Francis Crick were able to construct a molecular model of DNA that fits the X-ray data.
Their breakthrough discovery of the double-helix structure of DNA was based on the interpretation and analysis of existing data, combined with creative model building and hypothesis testing. This approach led to the famous elucidation of the DNA structure in 1953.