The $\alpha$ -Keratin Chains Indicated by the Diagram Below Have Undergone One

Multiple Choice

The $\alpha$ -keratin chains indicated by the diagram below have undergone one chemical step. To alter the shape of the $\alpha$ -keratin chains-as in hair waving-what subsequent steps are required?

A) chemical oxidation and then shape remodeling
B) chemical reduction and then chemical oxidation
C) chemical reduction and then shape remodeling
D) shape remodeling and then chemical oxidation
E) shape remodeling and then chemical reduction