Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to rid your house of odors [title] Check for a gas leak. [step] Is it a strong (especially sudden) " rotten eggs " smell? Heating and cooking gases such as propane and natural gas contain a noxious scent, in order to indicate a possible leak. This is a potentially dangerous situation.

Ending1: [substeps] Verify that gas leaks are seasonal, not summer and are generally not a threat to humans, pets, or small children. Check the toilet if you've seen it on the weekends, since you could be sick. Ending2: If using gas in your home is not safe for you, you may also want to consider using a gas kitchen appliance, like a gas stove. [title] Contact a professional if you suspect a gas leak. Ending3: [substeps] Be cautious when closing doors and windows. If the smell lingers after a few minutes, close your blinds or curtains, and turn off any lights or appliances to minimize visibility. Ending4: If this is a possibility : [substeps] Have all people exit the living quarters immediately. Open windows and doors to ventilate.

Answer format: ending1/ending2/ending3/ending4