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.