Choice C is correct.
Water molecules consist of two hydrogen atoms and one oxygen atom. Oxygen is an extremely electronegative atom, which means that it has the tendency to pull all electrons in the covalent bonding system towards itself. Because of this consistent increased presence of electrons around oxygen, it tends to be polar and negative.
As a result, the atoms which it is pulling the electrons from in the first place (which could be carbon or hydrogen for example), tend to have a positive polar charge since their electrons tend to exist closer to the oxygen atom than to themselves.
This polar nature of water allows it to dissolve many substances which are also polar in nature, however, the downside is that water cannot dissolve molecules which are non-polar such as fat molecules. This is because opposite charges attract, thus in order for water to be able to dissolve something, it has to be able to be attracted to the other molecules it is trying to dissolve. And since non-polar molecules do not tend to have charged characteristics like water, they do not dissolve in water, but in other non-polar solvents instead.
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