Write the next sentence in the following story.

How to cope with dry mouth
Drink plenty of water.
Dehydration is one of the most common causes of dry mouth. Sipping water can also help to relieve dry mouth when it is caused by disease or as a side effect of medication.

Options are:
1). Drink about 64 ounces of water every day or two to three times daily. At minimum, drink two to three cups of fluids daily..
2). Drink roughly eight glasses of water a day. For dogs, this should be eight to nine glasses daily..
3). You should aim to drink 64 ounces of water daily. You can adjust this by : Limiting your intake of fluids or electrolytes, which help you swallow less..
4). Doctors recommend drinking eight to twelve 8-ounce glasses of water each day to keep hydrated. Drinking too much water, however, can actually dissolve the mucus lining of the mouth and worsen the symptoms of dry mouth... The answer should be
4).