Concept:A logical paragraph starts with a general introduction, then explains specific details, followed by immediate outcomes, and ends with broader significance.
Explanation:Sentence 5 is the best opener because it states the overall breakthrough in genetics.
Sentence 1 names the scientists and year who proposed the model, directly building on the discovery.
Sentence 3 explains the key finding about base pairing, which is a specific mechanism.
Sentence 4 describes how this discovery revolutionised biology and led to advances in genetic engineering and biotechnology.
Sentence 2 concludes with the wide‑ranging impact on medicine, forensic science, and evolutionary research.
The correct order is 5 → 1 → 3 → 4 → 2, as it flows from general to specific to implications. Options B, C, and D mix this logical progression or start with a concluding sentence.
Answer:Option A: 5-1-3-4-2