the presence of more impurities in ice than in liquid water the ability of ice to float on liquid water the release of heat when liquid water turns into ice the cooling of liquid water as it flows over ice
I gave my students this multiple choice question: Water in the solid phase has a crystal structure which keeps molecules farther apart than water at certain temperatures in the liquid phase. This relationship explains which property?

Only one answer is correct among these 4 choices:
- the presence of more impurities in ice than in liquid water
- the ability of ice to float on liquid water
- the release of heat when liquid water turns into ice
- the cooling of liquid water as it flows over ice

Could you tell me which one is correct?

the ability of ice to float on liquid water