Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to treat oily hair [title] Wash regularly. [step] You should wash your hair at least once a day if your hair is oily. You may need to wash more often if it stays oily.

Ending1: [substeps] If you have a lot of oily hair, you can use a shampoo and conditioner made specifically for oily hair. Many body washes contain ingredients that can irritate oily hair. Ending2: Holding in oil may be difficult or even impossible, even with naturally oily hair. [substeps] Don't wash too often as this can affect hair follicles, especially if used. Ending3: Washing more often will help cut down on the oil. [substeps] Some people claim this step is the opposite of what you should do. Ending4: Washing too frequently can strip your hair of oils. Washing too often can work as well, because your hair will still produce oil.

Answer format: ending1/ending2/ending3/ending4