The building from the list provided with the highest likelihood of air pollution is a tightly sealed house with an unvented water heater. The school with leaks will let air exchange happen so that isn't it, and having a carbon monoxide detector only reports existing air pollution it doesn't prevent air pollution, it could have issues but we don't know. The tightly sealed house with the unvented water heater is a near sure thing.
Is it free choice answer or selecting the following?
Answer: A. Argue with your friend until he is convinced to give you the keys
Explanation: because you know how to drive and have not been drinking
The answer is D. Having Autoimmune Disease, the body doesn’t not recognize your own cells and foreign cells
