I think the answer may be water pollution.
water pollution > Water pollution<span> is the contamination of </span>water<span> bodies (e.g. lakes, rivers, oceans, aquifers and groundwater). This form of environmental degradation occurs when </span>pollutants<span> are directly or indirectly discharged into </span>water<span> bodies without adequate treatment to remove harmful compounds.
source: Wikipedia </span>
A large percentage of high-income<span> households and organizations. Is our answer!!</span>
<span>Definition: the medieval knightly system with its religious, moral, and social code.
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Synonyms:knight errantry, courtly manners, knightliness, courtliness, nobility<span>
Etymology: </span>
<span>Middle English: from Old French chevalerie, from medieval Latin caballerius, from late Latin caballarius ‘horseman’ </span>
