Which room in your house is most likely to have mold, an indoor air pollutant that can trigger asthma attacks and allergic reactions?

Respuesta :

Bathroom. Because of the moisture

when heater is on for long time without having ventilation then carbondioxide will be converted into carbon monoxide and causes air pollution.

So according to above explanation,

C. A tightly sealed house with an unvented water heater, is the correct answer.