Final answer:
The correct order of contributions made to the discovery of DNA is: DNA discovered > DNA studied with X-rays > 3D model of DNA developed > Human genetic code decoded > Present Day.
Step-by-step explanation:
- DNA discovered: Rosalind Franklin and other scientists used X-ray diffraction to learn about DNA's structure, discovering it.
- DNA studied with X-rays: Franklin's X-ray diffraction pattern of DNA helped elucidate its double helix structure.
- 3D model of DNA developed: James Watson, Francis Crick, and Maclyn McCarty developed a 3D model of DNA based on Franklin's work.
- Human genetic code decoded: The decoding of the genetic code began with the discovery of the three bases of DNA code for one amino acid and was completed by scientists like Marshall Nirenberg and Har Gobind Khorana.
- Present Day: The Human Genome Project started in 1990 and has led to the identification of genetic disorders and personalized treatment.
- 1800: This timeline does not show any relevant contributions to the discovery of DNA.