Which of the following does NOT require the application of barrier cream?

The choice indicating that a no base relaxer does not require the application of barrier cream is correct because no base relaxers are formulated in a way that minimizes the risk of irritation to the skin. These products contain ingredients that do not require a protective layer applied to the scalp or surrounding skin, as they are designed to be less irritating and can be safely used without the added barrier cream.

In contrast, chemical relaxers, hair color, and bleach can be harsh on the skin and often require the application of barrier creams to protect the skin from potential irritation, burns, or allergic reactions that can occur due to the strong chemicals they contain. The barrier cream acts as a protective layer, thus preventing these harsh substances from directly contacting the skin. This is particularly crucial in areas where skin is more sensitive, such as the scalp, ensuring safer application and reducing the likelihood of adverse reactions.