Please choose the correct ending to complete the given sentence: Health: [header] How to store essential oils [title] Store your oils in dark glass bottles. [step] Exposure to light can cause essential oils to oxidize rather quickly. As this happens, they typically lose their fragrance and any therapeutic qualities they may have had.

Ending1: Periodically storage and maintenance can help prevent the formation of these chemicals. In particular, look for bottles that are " cool and dark "--the latter is often the case, as these tend to hold the oils more on cooler days. Ending2: That will always be at a later date, while oils older than two or three years will still retain their scent as they age. Do not store oils in cool or dark glass bottles, as they should remain in the cool, dark part of the bottle. Ending3: Because of this, clear glass and plastic bottles should be avoided at all costs. [substeps] Amber and cobalt-blue glass bottles are fairly common. Ending4: They will still last for a few months, though, so a dark glass bottle is better for storing them in. [substeps] The room you're storing your oils in should be cool to the touch, but not hot.

Answer format: ending1/ending2/ending3/ending4