The correct answer is A) Water is best used for cooling of the chemical itself as well as surrounding areas. This is the best practice because chemical fires can react violently with water, potentially causing the fire to spread or creating toxic fumes. Applying water in a solid stream could cause the fire to flare up. Instead, water should be used to cool the chemical and surrounding areas to prevent the fire from spreading, rather than directly extinguishing the flames. The other options, such as applying water from opposing directions, in a solid stream, or as a spray, could be unsafe or ineffective for chemical fires.