From “The Discovery of DNA’s Structure” They were hardly modest, these two brash young scientists who in 1953 declared . . . that they had “found the secret of life.” But James Watson and Francis Crick’s claim was a valid one, for they had in fact discovered the structure of DNA, the chemical that encodes instructions for building and replicating almost all living things.

Watson and Crick’s discovery didn’t come out of the blue. As early as 1943 Oswald Avery proved what had been suspected: that DNA . . . carries genetic information. But no one knew how it worked.

[Then, in 1951 at] King’s College in London, Rosalind Franklin and Maurice Wilkins were studying DNA. Wilkins and Franklin used X-ray diffraction as their main tool—beaming X-rays through the molecule yielded a shadow picture of the molecule’s structure. . . .

Referring to Franklin’s X-ray image known as “Exposure 51,” James Watson is reported to have said, “The instant I saw the picture, my mouth fell open and my pulse began to race.” Shortly after, Watson and Crick made a crucial advance when they proposed that the DNA molecule was made up of two chains paired in such a way to form a double helix, like a spiral staircase.

For their work, Watson, Crick, and Wilkins received the Nobel Prize in 1962. Despite her contribution to the discovery of DNA’s helical structure, Rosalind Franklin was not named a prize winner: She had died of cancer four years earlier, at the age of 37.

Question 1 (1 point)
How does the information in these paragraphs contribute to the central idea of the article?

a
It emphasizes why Franklin and Wilkins believed that the X-ray image would inspire other scientists.
b
It explains the makeup of the DNA image known as “Exposure 51.”
c
It proves the accuracy of the author’s claim that the young scientists were quite brash.
d
It shows how the scientists depended on each other’s work to make their final discovery.