Which of the following is NOT a type of non-covalent interaction?

Covalent bonds are indeed not a type of non-covalent interaction. These bonds involve the sharing of electron pairs between atoms, resulting in a stable connection that is typically much stronger than non-covalent interactions. In contrast, non-covalent interactions, such as hydrogen bonds, van der Waals forces, and ionic interactions, are based on electrostatic attractions, dipole-dipole interactions, and temporary fluctuations in electron density. These types of interactions are generally weaker and more transient compared to covalent bonds, playing crucial roles in stabilizing structures like proteins and nucleic acids, as well as influencing molecular recognition processes. The distinctions between these interaction types are fundamental in biochemistry, highlighting the importance of non-covalent forces in biological systems.