After extensive reduction by heat, what should you apply to restore dehydration in the eye area?

To restore hydration in the eye area after extensive heat reduction, the most suitable choice is cavity fluid. Cavity fluid typically contains agents designed to retain moisture and can aid in hydrating tissues, which is especially important in sensitive areas like the eyes that may suffer from dehydration due to heat exposure.

Moisturizing lotion, while beneficial in various contexts, may not be specifically formulated for the unique needs of the eye area, often leading to inadequate results. Applying water might not penetrate the skin effectively or provide lasting hydration. Alcohol is dehydrating, which would exacerbate the dryness in the eye area rather than restore it. Thus, cavity fluid stands out as the most appropriate option to effectively address the issue of dehydration.