5
Answer: BSet 3: Command of Evidence
Explanation
PASSAGE
Water expands when it freezes, unlike most substances which contract. This is why ice floats on water. If ice sank, bodies of water would freeze from the bottom up, making it much harder for aquatic life to survive winter.
What is the ecological significance of ice floating?
A. It makes ice fishing impossible.
B. It protects aquatic life by keeping water liquid beneath the ice layer.✓ Correct
C. It causes flooding in coastal areas.
D. It increases evaporation rates in winter.
Detailed Explanation
The text states if ice sank, 'bodies of water would freeze from the bottom up, making it much harder for aquatic life to survive. ' Thus, floating ice protects life.
Key Evidence:
• "making it much harder for aquatic life to survive winter"
Why others are wrong: A (Ice fishing relies on ice floating; this is wrong.), C (Flooding is not mentioned.), D (Evaporation is not discussed.).