The correct answer is D) ice is less dense than liquid water because the molecules in ice are farther apart.
This makes sense because ice has to be less dense than liquid water because we know that ice floats on water. Objects denser than the liquid that they are placed in will sink, whereas if they are lighter than the liquid, they will float. The bonds in ice are more stable than they are in liquid water, which keeps the molecules farther apart. With less molecules per unit area than water, ice is the less dense of the two substances.
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