What environmental factor is associated with the use of fossil fuels according to the text?

The connection between fossil fuels and environmental impact primarily revolves around the pollution they generate. When fossil fuels are burned for energy, they release a variety of harmful substances into the air, contributing significantly to air pollution. This can lead to health problems for humans and environmental degradation. Additionally, the extraction and transportation of fossil fuels can result in water pollution, harming aquatic ecosystems and contaminating drinking water supplies. This fundamental relationship highlights why the use of fossil fuels is associated with both air and water pollution, making it the most accurate response regarding their environmental effects.