Concept:A logical paragraph starts with a general introduction, then moves to specific details, followed by the impact, and ends with a broader conclusion.Rule / Clue:Identify the sentence that introduces the main topic first. Then follow with who, what, how, and finally the long‑term effects.Explanation:Sentence 5 introduces the discovery of DNA’s double-helix structure as a major breakthrough. This sets the topic. Sentence 1 tells who made it (Watson and Crick) and how they used Rosalind Franklin’s work. Sentence 3 explains the key finding—how base pairing stores genetic information. Sentence 4 shows how this discovery revolutionized biology and led to genetic engineering. Sentence 2 concludes by listing the broad impact on medicine, forensics, and evolution. Thus the only logical order is 5-1-3-4-2.Answer:Option A: 5-1-3-4-2