Please choose the correct ending to complete the given sentence: Health: [header] How to avoid stomach problems in less developed countries [title] Boil untreated tap water for 1 minute to kill harmful microorganisms and make drinking safe. [step] The safest drinks are those that have been boiled, such as coffee or tea. All microorganisms are killed in temps above 200 degrees.

Ending1: [substeps] Investigate the types of water which contain these solutions--cool or cold tap water (ph 2.0), filtered water, bottled or conventional tap water. If the water is not sterile, this is considered safe. Ending2: [title] Never add ice to any drink, and don't use tap water to brush your teeth. [title] Stick to bottled beverages, including soft drinks, bottled beer, wine and bottled water, but only if the containers have been brought to you unopened. Ending3: [title] Refrigerate everything you eat in an ice bath. [step] Cold water soaks up microorganisms and dehydrates them. Ending4: [title] Give your body a " shock " or radiating blast of attack with water. [title] Replace bottled, replenished water every time you can't even clean yourself.

Answer format: ending1/ending2/ending3/ending4