Please choose the correct ending to complete the given sentence: Health: [header] How to deal with being allergic to cats [title] Create a cat-free zone. [step] Your bedroom is your castle. Defend it from allergens at all costs! If you can keep the cat out of your bedroom, you create an (mostly! ) allergen-free zone at night.

Ending1: [substeps] Cover your windows, shut off the air conditioning, and close the blinds. Block outside sources of the allergen causing the allergy. Ending2: That gives your system a chance to recover overnight. [substeps] If you're looking for a moat to defend your bedroom, consider a hepa filter. Ending3: Invest in an allergy-friendly bag. You can spread this protection around your bedroom--anything from other pet accessories, to curtains that cover a window, blinds that close, and down curtains (if you have carpet in your bedroom). Ending4: Try to make sure the place is completely dust free, with no allergens. [substeps] Some environmental factors that can suppress allergy are: soil, dust levels, dust in air and temperature.

Answer format: ending1/ending2/ending3/ending4