Question

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

Answer 1

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.

Answer 2

Bathroom. Because of the moisture