Homeowners planting trees is to neighbors dealing with fallen leaves as factories polluting air is to ___?

Homeowners planting trees can create a beautiful environment, but their fallen leaves can be a hassle for neighbors, similar to how factories that pollute the air might negatively impact the health and enjoyment of nearby residents. In this case, the negative externality is the unwanted side effect of a homeowner's decision, just like the pollution from factories affects the community. For example, if a factory releases smoke and chemicals into the air, people living nearby might experience health problems or have to deal with dirty air. This connection shows how one person's actions can impact others in ways they might not consider. Therefore, the answer to the analogy is that factories polluting air is to neighbors suffering from poor air quality.