During a permanent wave, what is the primary chemical change and which bond is manipulated?

• A. Breaking and reforming disulfide bonds in the cortex; reducing agents break them to form sulfhydryl groups, and oxidizers in the neutralizer re-form them in the new curl pattern.
• B. Breaking salt bonds and reforming hydrogen bonds.
• C. Swelling the hair shaft without chemical change.
• D. Breaking keratin peptide bonds permanently to loosen the curl.

Answer: (A)