Quaternary structures of proteins include different protein and non protein moiety to work together.
Option B
Proteins are the polymer of amino acids which are formed after several processing. The polypeptide chains are formed when the transcripted mRNAs are translated in the Ribosomes to produce the polypeptide chains. Then they are further processed by slicings and adding and cutting of several protein parts to this main polypeptide chains and they are slightly folded by means of hydrogen bonds between the polypeptide chain atoms to give a slightly coiled structure. Now this secondary polypeptide undergoes several structural modifications by chaperon proteins which introduce different ionic, disulphide, covalent etc bondings between different parts of polypeptide chain to produce a highly coiled tertiary structure.
Now in some proteins like haemoglobin, there are the protein part i.e globin associated with haem chains, which is the Quaternary structure of proteins. It's formed when different proteins are together associated to perform a particular function.