Fact 1: Hydrogen bonds cause water to expand when it freezes. Fact 2: Water is everywhere H20. Given the two facts above, what causes H20 to expand when frozen?

Possible answers:
(A). evaporation;
(B). vaporization;
(C). hydrogen bonds;
(D). helium bonds;
(E). mysterious forces;
(F). nitrogen bonds;
(G). Physical weathering;
(H). precipitation;
Answer:
(C).