Answer:
Erwin Chargaff
Explanation:
Erwin Chargaff found that in DNA, the ratios of adenine (A) to thymine (T) and guanine (G) to cytosine (C) are equal.
(dnalc.cshl.edu)
These base pair relationships are often called Chargaff's rules of DNA base pairing, named after the Columbia University scientists who observed that there are equal molar concentration of A & T, as well as G & C in most DNA molecules.
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