Please choose the correct ending to complete the given sentence: Home and Garden: [header] How to use a humidifier [title] Choose the right type of humidifier for your needs. [step] There are many different types of humidifiers on the market, so finding the best humidifier for your needs and circumstances is very important. A few of the most common humidifiers include : [substeps] Central humidifiers.

Ending1: These are housed in a structure of ceramic or plastic and normally installed separately from all other humidifiers of that kind. Central humidifiers are designed and installed so that they are not exposed to light. Ending2: Central humidifiers have a cubbycone (or raised back end) and pvc mesh that wicks away moisture and lowers mildew. They can be found at home improvement stores and are germ-free. Ending3: These are humidifiers that have internal vents, which means the air in your humidifier is drawn out through the vent. Air inside the humidifier units has to be plugged in so that the air can escape into the room. Ending4: Central humidifiers are used to humidify an entire house. They are built into the house's heating and cooling system.

Answer format: ending1/ending2/ending3/ending4