Who are the two scientists credited with discovering the structure of DNA?

• A. Rosalind Franklin and Maurice Wilkins
• B. James Watson and Francis Crick
• C. Linus Pauling and James Watson
• D. Charles Darwin and Alfred Wallace

Answer: (B)

James Watson and Francis Crick are the scientists credited with discovering the DNA structure. They proposed the double helix in 1953, a model that neatly fit Chargaff’s rules—A pairs with T and G pairs with C—and matched the X-ray diffraction data that suggested a helical, uniform-width molecule. Their final picture shows two antiparallel strands forming a right-handed helix, with the sugar-phosphate backbone on the outside and base pairs stacked inside. This arrangement explains how genetic information can be copied: each strand can serve as a template to build its complement, leading to semi-conservative replication. While Rosalind Franklin and Maurice Wilkins provided crucial experimental data that supported the helical structure, Watson and Crick are the ones widely credited with the discovery, with Franklin’s contributions acknowledged as foundational to the model.