Red Seal Cosmetology Practice Exam 2026 – Your All-In-One Guide to Exam Mastery!

The most common types of chemical hair relaxers are actually B and D sodium and no-lye. While A and C (ammonium and lye) have also been used in the past, they are now considered less common and less popular options due to their harsh chemicals and potential to cause hair damage. Therefore, option A is incorrect as it is not one of the most common types of chemical hair relaxers.