Answer:
The correct answer will be option-B.
Explanation:
The information about DNA we know today form what, structure and functional aspects is the result of the contributions of the discoveries made by the scientists in the past.
The story of DNA begins with the identification of molecule by Johann Friedrich Miescher in the 1860s, identification of its monomers by Albrecht Kossel in 1881, functional role as the genetic material of the organism by the experiments of Hershey and Chase in 1928 and the double-helical model by Watson and Crick shows in 1953 and many other related discoveries by other scientists shows us that new discoveries are made on the basis of work of the other scientists which live or lived in the past.
Thus, Option-B is the correct answer.
The history of the discovery of DNA as genetic material of the organisms konwn to us today statred in 19th century when
Johann Friedrich Miescher
1860s
Chromosomes were first observed in plant cells by Swiss botanist Karl Wilhelm von Nägeli in 1842,
Felice Fontana discovered the nucleolus in eel cells in the year 1774
Hershey-Chase experiment shows that DNA
James Watson & Francis Crick suggest the first correct double-helix model of DNA structure