This ribbon diagram represents a protein in water. even without showing the side chains, it's clear that the protein's quaternary structure

It seems that you have missed the necessary options for us to answer this question, so I had to look for it. Anyway, here is the answer. Based on the ribbon diagram that represents a protein in water, it's clear that the protein's quaternary structure is not present. Therefore, the answer is none of the above. Hope this helps.

The answer for this is a

In any atom of any element, you will find protons and neutrons in the nucleus of any atom