Question

1. an important clue to the structure of dna was provided by

a. a protein analysis of a muscle cell.
b. an x - ray diffraction photograph of dna.
c. an mri image of a brain cell.
d. a microscopic examination of a fruit fly.

Explanation:

Rosalind Franklin's X-ray diffraction photograph (Photo 51) of DNA provided critical data about its helical, double-stranded structure, which was key to Watson and Crick's model of DNA. The other options are unrelated to discovering DNA's structure.

Answer:

B. an X-ray diffraction photograph of DNA.