What best describes a feature of a covalent bond?

A covalent bond is best described by the feature of atoms sharing electrons. This sharing occurs when two or more nonmetal atoms come together to achieve a full valence shell, which is critical for stability. By sharing their outermost electrons, these atoms can bond effectively, allowing them to fulfill the octet rule or achieve a more stable electron configuration.

In contrast, some other bonding types involve different interactions. For example, ionic bonds are characterized by the transfer of electrons from one atom to another, typically between metals and nonmetals, which is not the case with covalent bonds. The pooling of electrons might refer to metallic bonds, where electrons are shared more freely among a lattice of metal atoms, but it does not specifically describe covalent bonds. Lastly, covalent bonds frequently occur between nonmetals rather than exclusively between metals, making it incorrect to restrict their occurrence.