16Hit1600
Information and IdeasHardInference from a biological signal

Information and Ideas practice question

Fossil leaves from the region carry far more tiny pores on their surfaces than leaves of the same species do today. Plants grow more pores when the air holds less carbon dioxide. The fossils therefore suggest that ____

Which choice most logically completes the text?

  1. A. the air held less carbon dioxide when the fossil leaves grew than it does now.Correct
  2. B. the fossil plants grew in darkness.
  3. C. carbon dioxide levels have not changed since the fossils formed.
  4. D. the fossils belong to a different species from today's plants.

Answer: A. the air held less carbon dioxide when the fossil leaves grew than it does now.

More pores means less carbon dioxide; the fossils have more pores; so the ancient air had less.

Why the other answers are wrong

B. the fossil plants grew in darkness.
Light isn't part of the reasoning.
C. carbon dioxide levels have not changed since the fossils formed.
The difference in pores implies a change.
D. the fossils belong to a different species from today's plants.
The text says the fossils are the SAME species.

More Information and Ideas questions

Not affiliated with the College Board. SAT is a trademark of the College Board.