<span>Watson and Crick determined the base pairing by using the new information to construct a new double-stranded helix model with the nitrogen bases paired A to T and C to G in the center. This base pairing immediately suggested to Crick that one side of the molecule could serve as a template to exactly replicate DNA sequences to pass on genetic information during cell reproduction. This second, successful model was unveiled in February 1951.</span>
I believe it’s melanin , if I’m not mistaken.
Answer:

Explanation:
The formula for density is ρ
(where
represents mass, and
represents volume).
With this formula, we can calculate the density of the object:
ρ 
Hope this helps :)
The answer is D. Have a great day
Its none of them The person who actually disporved it was Charles Wyville Thompson