Which of the following investigators was/were responsible for the following discovery?

In DNA from any species, the amount of adenine equals the amount of thymine, and the

amount of guanine equals the amount of cytosine.

A) Frederick Griffith

B) Alfred Hershey and Martha Chase

C) Oswald Avery, Maclyn McCarty, and Colin MacLeod

D) Erwin Chargaff

E) Matthew Meselson and Franklin Stahl

Answer:D

Explanation:

It was Erdwin Chargaff an Austrian biochemist that proposed the base pairing rule. He studied the ratio of purine to pyrimidine nucleotides in different cells and species and concluded that the ratio of purine to pyrimidine is 1:1 from any cell of an organism.

Chargaff rule state that the number of purines is equal to the number of pyrimidines in individuals of the same specie.

Chargaff's base pairing rule Adenine equals thymine and guanine equals cytosine. Always the DNA two strands are complementary to each other. So the adenine of one strand will pair the thymine of the opposite strand, while the quanine will pair with cytosine