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Correct Answer: Option (C) — The density of water is maximum at 4°C
Concept & Option Breakdown
Standard Reference VerifiedWater exhibits anomalous expansion between 0°C and 4°C, reaching its maximum density at 4°C. As surface water cools toward 4°C, it becomes denser and sinks to the bottom. Once the entire water body reaches 4°C, further surface cooling (0°C–3°C) makes water less dense, keeping it at the surface where it eventually freezes into an insulating layer of ice, leaving denser liquid water at 4°C at the bottom.
Anomalous density behavior of water at 4°C is the fundamental physical property explaining aquatic survival under frozen lakes.
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