Question

the diagram shows water at the molecular level. what property of a water molecule allows hydrogen bonds to form among adjacent molecules?
3 points
the ionic bonds that form after the molecule separates into a hydroxide ion (oh - ) and hydrogen ion (h + ).
the polarity of the molecule, which involves a slightly negative oxygen atom and slightly positive hydrogen atoms
the small size of the two hydrogen atoms compared to the oxygen atom.
the strong covalent bonds that hold the oxygen atom to each hydrogen atom

Explanation:

Hydrogen bonds form due to the polarity of water molecules. The oxygen atom is more electronegative than hydrogen, creating a slightly negative charge on oxygen ($\delta -$) and slightly positive charges on hydrogens ($\delta +$). Opposite partial charges ($\delta +$ of one molecule's H and $\delta -$ of another's O) attract, forming hydrogen bonds. Ionic bonds (when water dissociates) are not related to hydrogen - bond formation among adjacent undissociated molecules. The size of atoms (small H vs O) doesn't directly cause hydrogen bonding. Strong covalent O - H bonds are within a water molecule, not responsible for inter - molecular hydrogen bonds.

Answer:

the polarity of the molecule, which involves a slightly negative oxygen atom and slightly positive hydrogen atoms