Concept:The passage discusses how biology, though the youngest science, gained importance later, while physics and chemistry progressed faster and are more visible.
Explanation:S1 states biology is the youngest natural science.
S follows logically: it says physics and chemistry progressed faster than biology.
R adds that applications of physics and chemistry are also more visible in daily life. The word 'also' in R connects it to S.
P begins with 'However', contrasting with R and S. It says that the 20th and 21st centuries showed biology's utility in health and agriculture.
Q provides examples of that utility: antibiotics, synthetic drugs, and anaesthetics have improved medical practice and human health.
S6 concludes that life expectancy has dramatically changed, linking to the impact of biological advances mentioned in Q.
Thus, the only sequence that matches the logical flow is SRPQ.
Answer:SRPQ (Option D)