The correct option is A Ester bonds
Protein folding is the process by which a protein structure assumes its functional shape or conformation by allowing interaction between amino acids by various bond formations. All protein molecules are heterogeneous unbranched chains of amino acids. Different types of weak interactions hold the interacting segments together in protein. Hydrophobic interaction, H bonds, and electrostatic interactions are the weak ones and stabilize the tertiary structure of proteins while ester bonds are covalent bonds and are least likely to be involved in stabilizing the three dimensional folding of most proteins. So, the correct answer is option A.