During the denaturation of proteins the primary structure stays intact.
Therefore, the correct option is (A): Primary
Given below are two statements:
Biomolecules are the most essential organic molecules, which are involved in the maintenance and metabolic processes of living organisms. These non-living molecules are the actual foot-soldiers of the battle of sustenance of life.
There are four major classes of Biomolecules – Carbohydrates, Proteins, Nucleic acids and Lipids.