Hydrogen bonds are important for which of the following reasons?

Hydrogen bonds play a critical role in contributing to the unique properties of water, making option C the correct choice. Water molecules are polar, with a partial positive charge on the hydrogen atoms and a partial negative charge on the oxygen atom. This polarity allows hydrogen bonds to form between the molecules, resulting in several vital properties: high surface tension, high specific heat, and solvent capabilities that are crucial for life.

These hydrogen bonds are not strong compared to covalent bonds, but their collective strength is significant. For instance, the hydrogen bonds that form between water molecules allow for cohesion (the attraction of water molecules to each other) and adhesion (the attraction of water molecules to other substances). This is essential in biological systems, as it enables processes like capillary action and the ability of water to dissolve many substances crucial for biochemical reactions.

In contrast, the other options do not accurately reflect the role of hydrogen bonds. Metals rely primarily on metallic bonding rather than hydrogen bonding for their solid structure. High-energy reactions in cells are primarily facilitated by covalent bonds and other forms of energy transfer rather than hydrogen bonds. Additionally, while hydrogen bonds are important for protein structure, particularly in secondary structures like alpha helices and beta sheets, they do not form the backbone of proteins