Which statement accurately defines protein denaturation and its effect on structural levels?

Denaturation only affects membrane proteins and leaves soluble proteins unaffected; it is primarily a reversible phosphorylation-driven process.

Denaturation alters a protein's secondary through quaternary structures (unfolding or aggregation) while leaving the primary amino acid sequence intact; common causes include heat, extreme pH, mechanical agitation, and salt concentration changes.

Denaturation permanently removes amino acids from the primary sequence and selectively strengthens secondary and tertiary structures, typically caused by gentle temperature decreases.

Denaturation converts proteins into nucleic acids by breaking peptide bonds and re-synthesizing bases, primarily due to exposure to ultraviolet light only.