Most biochemical macromolecules are polymers, which are chains of what?

Most biochemical macromolecules are indeed polymers, which are made up of chains of repeating units known as monomers. These monomers can vary depending on the type of macromolecule being formed. For instance, proteins are composed of amino acid monomers, nucleic acids are made from nucleotide monomers, and polysaccharides consist of sugar monomers. This fundamental structure of being formed from smaller, identical or similar building blocks is what defines a polymer.

The other options represent specific types of macromolecules or their components rather than the basic building blocks themselves. Complex carbohydrates and proteins are examples of macromolecules created from chains of repeating monomers, while fatty acids are not polymers but rather components that form lipids, a different class of macromolecules. Thus, focusing on the concept of polymers as chains of repeating monomers is what solidifies the understanding of how most biochemical macromolecules are structured.