What is the most effective means of controlling current water pollution of us surface waters

It is shutting down factories that discharge materials to rivers, I am certain of it, because factors dump their waste in our waters, because they are a US Companies, and don't have the right to dump into international waters. Come on don't you remember any of that, companies dumping in our waters etc.

Answerδh > 0explanationc₆h₆  (s)  → c₆h₆ (l)if you are changing it from a solid to a liquid, you are pretty much melting the solid. this requires heat energy. therefore, the reaction is endothermic (takes in energy); the system enthalpy increases as the reaction proceeds: δh > 0.

Um i think answer is a