4
Answer: BSet 4: Inferences
Explanation
PASSAGE
Scientists studying the Arctic have found that polar bear skulls have become smaller over the past 30 years. The researchers correlate this change with reduced ice coverage, which has forced bears to swim longer distances and hunt less efficiently.
What can be inferred about the relationship between ice loss and polar bears?
A. Ice loss has no effect on polar bear populations.
B. Environmental changes may be affecting polar bear physical development.✓ Correct
C. Polar bears are thriving due to climate change.
D. Polar bears prefer swimming to walking on ice.
Detailed Explanation
Smaller skulls correlate with ice loss and reduced hunting efficiency—environmental changes affecting physical traits.
Key Evidence:
• "skulls have become smaller"
• "correlate with reduced ice coverage"
Why others are wrong: A (Physical changes prove effects exist.), C (Smaller skulls + less efficient hunting = not thriving.), D (Forced to swim (not preference) implies stress.).