hard · SAT Reading & Writing

In the late Carboniferous period, atmospheric oxygen levels reached nearly 35 percent, far higher than today's 21 percent. Since the size of an insect is limited by the distance oxygen can diffuse through its tracheal system, these hyperoxic conditions allowed for the evolution of giant arthropods. However, current research suggests that while high oxygen facilitates larger bodies, it also increases the risk of oxygen toxicity in larvae, which lack the sophisticated metabolic regulation of adults.

Which choice most logically completes the text?

  1. Giant insects would have been unable to survive if oxygen levels had dropped below 30 percent during the period.
  2. Max insect size in the Carboniferous was capped by a trade-off between respiratory efficiency and larval survival.
  3. Oxygen toxicity was the primary cause of the eventual extinction of giant arthropod species in the Permian period.
  4. Larval insects in the Carboniferous period evolved unique respiratory organs to combat the effects of high oxygen.

Sign up free to see the explanation and track your rank →

More SAT Reading & Writing practice

KomFi: Test Prep Made Easy

KomFi: Test Prep Made Easy — free adaptive practice for GMAT, GRE, SAT, ACT, National Real Estate Exam, Investment Banking, and finance with full explanations.

KomFi Academy is free GMAT prep and personalized GMAT help built as a training platform: 89,613+ practice questions, 30,000+ flashcards, on-demand video lectures, podcasts, and 4K slide decks. Flagship tracks: Free GMAT Prep, Free GMAT Resources, National Real Estate Exam Prep, Investment Banking Prep, Finance Prep, GRE, SAT, ACT, LSAT, MCAT, Financial Accounting, Private Equity, Private Credit, and Quantitative Finance.

Free GMAT Prep & Personalized GMAT Help

What's inside

Topics

View pricing · Read testimonials