Air pollution and water pollution are more often regional problems than global problems. Water pollution involves the contamination of water bodies such as rivers, lakes, oceans, and groundwater; usually caused by human activities. Air pollution is the release of pollutants into the air; harmful or excessive quantities of substances such as gases, biological molecules, and particulates.
The correct answer would be C. They combine to form atoms.
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Due to a page error, I attach the answer in a word file.
The right answer is water.
A solution is a liquid containing several constituents
* The majority constituent is called solvent. Most often consists of water, the solution is called aqueous solution.
* The substances in solution are called solutes.
* The species in solution are either molecules or ions.
If we add water in the aqueous solution, we will have a dilution. On the contrary, if we add solute or remove water (pure water in solutes) we will have a concentration.