Fact 1: Hydrogen bonds cause water to expand when it freezes.

Fact 2: Deuterium, or heavy hydrogen, is an isotope of hydrogen, or a hydrogen atom with a neutron added.

Given the two facts above, answer the question "The bonds of that which when heavy is Deuterium cause what to expand when it freezes?" with the following options: 
- matter
 - rings
 - CO 2
 - liquids
 - gas
 - solutes
 - cations
 - water


 

        water 