Inferences
SAT Reading & Writing · Rachel · Class 06 · October 10

Inferences

The Gap the Facts Leave

  • StemWhich choice most logically completes the text?
  • Sub-typeInferences — the conclusion the facts point to
  • ThemeNatural science → evolution → why deep sleep is widespread
  • PointThe text stops at a blank in its last sentence. The words before the blank (imply that, suggest that, most likely indicates that) say whose conclusion it is and how firm it may be.
  • PointThe conclusion fills the gap the facts leave, one step past them.
Question 1
Many animals, including humans, must sleep, and sleep is known to have a role in everything from healing injuries to encoding information in long-term memory. But some scientists claim that, from an evolutionary standpoint, deep sleep for hours at a time leaves an animal so vulnerable that the known benefits of sleeping seem insufficient to explain why it became so widespread in the animal kingdom. These scientists therefore imply that ______

Which choice most logically completes the text?

  1. prolonged deep sleep is likely advantageous in ways that have yet to be discovered.
  2. most traits perform functions that are hard to understand from an evolutionary standpoint.
  3. it is more important to understand how widespread prolonged deep sleep is than to understand its function.
  4. many traits that provide significant benefits for an animal also likely pose risks to that animal.
Worked Answer

A. prolonged deep sleep is likely advantageous in ways that have yet to be discovered.

  1. Facts with their limits: sleep has known benefits (healing, memory); deep sleep for hours leaves an animal very vulnerable; the known benefits “seem insufficient to explain why it became so widespread.”
  2. The gap, in the text’s own frame (“from an evolutionary standpoint”): a costly trait that became widespread must have paid for its cost, and the known benefits do not cover it. So the scientists are pointing at benefits that are not yet known. “Therefore imply that” makes the blank their own conclusion, one step past the facts.
  3. Smallest conclusion in your own words: “more benefits than we know.” A says exactly that, about this one trait, with “likely” keeping the degree open.
Method from Question 1
  • Recognize the form: a blank ends the text, and the lead-in before it (therefore imply that) names whose conclusion it is.
  • List the facts with their limits: known benefits; hours of vulnerability; the known benefits seem insufficient to explain why the trait is widespread.
  • Name the gap the facts leave: a widespread trait must be worth its cost, and the known benefits do not cover it. The smallest conclusion fills exactly that gap: there is more benefit than is known.
  • Stay with the one thing the text discusses. A choice that turns one trait into most traits or many traits adds a population the text never covers; a choice that says what is more important to study adds a recommendation.