What must be applied to the entire scalp before a relaxer application?

Before applying a relaxer, it is essential to use base cream on the entire scalp. Base cream serves as a protective barrier, helping to prevent irritation and chemical burns that can occur from the harsh chemicals in relaxers. By applying base cream, you create a safeguard for the sensitive skin on the scalp while allowing the relaxer to effectively work on the hair shaft.

The other options, while they may offer benefits for hair care or conditioning, do not provide the specific protective function that base cream does during the relaxer process. Leave-in conditioners, hair oils, and moisturizing sprays are generally designed for hydration and nourishment rather than protection from chemical treatments. Thus, base cream is specifically intended for this purpose in the relaxer application process.