Massachusetts Board of Cosmetology Practice Exam

A tint back service refers to the process of reverting dyed or lightened hair to its original or natural color. This means that options A and D are incorrect because they involve a change in hair color, while a tint back service is specifically about returning to the original color. Option B, which involves straightening hair, is also incorrect as it does not mention anything about color. Therefore, option C is the most specific and accurate choice.