The best source of carbon monoxide among the given options is vehicle exhaust, as it is produced from the incomplete combustion of fuel in engines. Other choices, like household products and solvents, are not major sources of carbon monoxide. Thus, the correct answer is B: vehicle exhaust. ;
The best source of carbon monoxide among the provided options is vehicle exhaust, as it is produced from the incomplete combustion of fuel in engines. Other options like household cleaning products, nail polish remover, and paint thinner are not significant sources of carbon monoxide. Thus, the correct answer is B: vehicle exhaust.
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