Please choose the correct ending to complete the given sentence: Health: [header] How to improve your home's air quality [title] Understand the risk of poor air quality at home. [step] Immediate effects include irritation of the eyes, ears, nose, and throat. These symptoms may present as a common cold, or allergies, but should fluctuate.

Ending1: If prolonged exposure to new or unusual odors bother you or cause allergies, then evacuate your home immediately. [title] Keep your air properly ventilated if used to treat chronic conditions. Ending2: Answer any questions that come up about your home's air quality from experts before making an appointment with an allergist. [substeps] Get a general honest opinion about your home's air quality and not just your family's. Ending3: A house with poor air quality can quickly become infected with a potentially untreatable illness such as crohn's disease or sinus infection. [title] Ask your doctor about germs. Ending4: [substeps] Long-term effects include the possibilities of respiratory disease, cancer, and heart disease. Currently, research is underway to determine precisely what level of certain pollutants cause these effects.

Answer format: ending1/ending2/ending3/ending4