What is hydrogen bonding primarily characterized by?

Hydrogen bonding is primarily characterized by the electrostatic attraction that occurs when a hydrogen atom, which is covalently bonded to a highly electronegative atom (such as nitrogen, oxygen, or fluorine), interacts with the lone pair of electrons on another electronegative atom. This attraction results from the partial positive charge on the hydrogen atom due to the electronegativity difference, which creates a strong dipole.

This highly directional and relatively strong interaction plays a crucial role in determining the properties of substances, such as the high boiling point of water compared to similar-sized molecules. In contrast, the other options do not accurately capture the essence of hydrogen bonding; they either describe interactions that do not involve the critical role of electronegative atoms or misrepresent the fundamental nature of the bonding involved.