Pollution occurs when impurities enter the land, water or air. An oil spill deep in the ocean will to water pollution only. Spraying aerosols will lead to air pollution only. Water and land pollution will occur when there is a landfill leaking above and below the ground. Soil erosion near a clean water source will cause air, land and water pollution.
Mid-ocean ridges form along divergent boundaries aka where two plates are pulling away for one another so I'm assuming it's A "Where two oceanic plates move apart"
