Set 4: Inferences (Intermediate)
Explanation
PASSAGE
Studies show that exercise promotes neurogenesis—the creation of new brain cells—in the hippocampus, a region associated with memory. Paradoxically, some researchers have questioned whether these new cells actually integrate into functional circuits, as the evidence for cognitive improvement from adult neurogenesis remains mixed.
What can be inferred about exercise and brain health?
Detailed Explanation
This question asks you to draw a logical conclusion from the text. New cells are created but functional integration and cognitive benefit are 'questioned' and 'mixed'—still verifying. A valid inference must be supported by evidence in the passage, even if not stated directly. Look for clues in the text that strongly suggest the answer. Avoid conclusions that require assumptions beyond what's written. Valid inferences are strongly supported by multiple pieces of evidence in the text. Be cautious of choices that go too far beyond what the passage actually states. The best inference is the one most directly supported by textual evidence.
Key Evidence:
• "questioned whether cells integrate"
• "evidence remains mixed"
Why others are wrong: A (Neurogenesis occurs 'in the hippocampus.'), C ('Some researchers' are still questioning = ongoing study.), D ('Mixed evidence' means not definitive.).