posted by henry .
since the 1970s the united states and canada have reduced _______ around lake erie. A)unregulated boat traffic b)overgrowth of destructive algae c) noise pollution D)illegal immigration. i think it b please help me out.
Lake Erie was heavily polluted by agricultural runoff (and other things as well). Such pollution tends to cause excessive algae growth. Therefore I would guess destructive algae, although I do not know. I am however quite sure the other choices are wrong.