Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to treat kidney disease in cats [title] Use medications to repair toxin damage to the stomach wall. [step] When a cat has kidney disease, there are raised levels of urea and phosphate in the blood, which are particularly irritating to the stomach lining and the gums. This may result in ulceration, which can be seen as inflamed, ulcerated tissue on the gums or tongue.

Ending1: Fortunately, the clogged inflamed blood vessels allow the cat to expel large amounts of urea. [substeps] If the ulceration is severe, the cat may need surgery. Ending2: This fluid needs to be removed and cleaned throughout the day. [substeps] Stage 3 kidney failure includes vomiting or diarrhea, and does not involve surgery or any other treatment. Ending3: [substeps] Pills are a likely method of repairing the integrity of the kidney wall. These pills are made of magnesium and water, which help to repair fluid around the kidneys. Ending4: It can also produce stomach ulcers. [substeps] If the cat is vomiting, and in particular if the cat is vomiting blood, it may be assumed that the cat is suffering from gastric ulcers.

Answer format: ending1/ending2/ending3/ending4