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Rosalind Franklin

APBIO-GH4JFE

Rosalind Franklin produced an X-ray image that helped Watson and Crick determine the width of a DNA molecule.

Which of the following BEST explains what this information helped them realize?

A

Bonding between two purines would be consistent with the diameter of the DNA helix.

B

Chargaff’s Rule did not apply to the DNA molecule.

C

Bonding between a purine and pyrimidine would be consistent with this width of a DNA helix since each rung has a three-ring molecular dimension.

D

Adenine must bond with cytosine, and guanine must bond with thymine on each rung of the DNA ladder to accommodate for a proper diameter of the double helix.