Which statement best describes how Watson and Crick's model used other scientists' work to create a model...

Which statement best describes how Watson and Crick's model used other scientists' work to create a model of DNA?
They used Chargaff's rule to determine that it contains ribose sugar.
They used Franklin's photo to determine that DNA was a double helix.
They used Levene's work to determine the number of base pairs in each strand.
They used Nirenberg and Matthaei's studies to determine that DNA is made of nucleotides.