Final answer:
For braiding straight, resistant hair, it is advisable to use a conditioning serum to make the hair more pliable, rather than hair spray which is designed to hold styles in place.
Step-by-step explanation:
To make straight, resistant hair more pliable for braiding, it is recommended to braid it slightly damp or with a light coating of a different product such as wax or a conditioning serum. Conditioning serums are generally used to smooth the hair and provide flexibility, which helps in managing and styling the hair. Unlike hair spray, which stiffens the hair, serums help soften the hair, making it easier to work with for styling practices like braiding.
When considering the options provided in the context of braiding hair, the answer would be A) a conditioning serum. Hair gel and hair mousse are typically used for holding a style in place, and while they can add some pliability, they might not be as effective as a serum for this purpose. A heat protectant spray is usually applied before using heat styling tools to prevent damage to the hair but is not specifically designed to increase hair's pliability for braiding.