How many members of the board must be at least 21 years of age and not engaged in cosmetology?

The correct choice highlights that at least two members of the board must be at least 21 years of age and not engaged in the practice of cosmetology. This requirement ensures that there is a degree of impartiality and diverse perspective on the board. By including members who are not actively engaged in cosmetology, the board can incorporate a broader view that can represent the interests of the public rather than only the interests of cosmetologists. This aligns with the goal of regulatory boards to safeguard public health and welfare while also providing oversight to the profession.

Having a defined number of non-cosmetology engaged members is crucial in maintaining a balance between industry representation and consumer protection, allowing decisions to be made that are fair and just, ultimately benefiting both the professionals in the field and the consumers receiving those services.