One advantage of quaternary structure in proteins is that:

The advantage of quaternary structure in proteins primarily relates to how multiple polypeptide chains, or subunits, come together to form a functional protein complex. The quaternary structure enables these subunits to interact and assemble more easily, allowing for a coordinated function that might be more complex than what a single polypeptide chain can achieve on its own. This multi-subunit assembly often leads to increased stability, regulatory control, and the ability to carry out allosteric effects, where the binding of a molecule to one subunit can influence the activity of another.

In contrast, the other options do not accurately describe the advantages of quaternary structure. The idea that it enhances a protein's color pertains more to specific chromophoric properties rather than structural advantages. Assembling from subunits is indeed easier, but claiming it eliminates the need for folding misunderstands the necessity of proper folding for each individual subunit. The concept that quaternary structure prevents protein degradation is also misleading, as protein stability against degradation depends more on a variety of factors including structural integrity, surrounding environment, and cellular conditions rather than solely on the quaternary structure itself. Thus, the characterization of quaternary structure facilitating the assembly of subunits is a key