The sharp transition seen in Figure suggests that A. Proteins can be denatured by any treatment that disrupts the weak bonds stabilizing tertiary structure, such as heating, or by chemical denaturants such as urea or guanidinium chloride. B. A comparison of the degree of unfolding as the concentration of denaturant increases reveals a sharp transition from the folded, or native, form to the unfolded, or denatured form, suggesting that only these two conformational states are present to any significant extent. C. A similar sharp transition is observed if denaturants are removed from unfolded proteins, allowing the proteins to fold. D. Protein folding and unfolding is an “all or none” process that results from a cooperative transition . -triyambak.org