Final answer:
Improperly stockpiled or illegally dumped tires lead to environmental pollution by taking up landfill space, providing habitats for pests, and potentially contaminating soil and water.
Step-by-step explanation:
When tires are improperly stockpiled or illegally dumped, the correct answer is B. They contribute to environmental pollution. Tires do not decompose quickly and become a significant environmental problem. As they accumulate, they take up a large amount of space in landfills and provide breeding grounds for mosquitoes and other pests. Furthermore, when tires are illegally dumped, they can contaminate soil and water sources through leachates, especially if they catch fire which releases toxic compounds into the air. The practice of tire recycling is encouraged because it helps reduce the consumption of raw materials and the volume of waste materials that must be treated and disposed of safely.