OPTIONS:
(i) Make sure that your dog's water bowl is and properly fitted with a water bottle. Check the bottles at your pet store and make sure that your dog's bowl has correctly fitted and is a proper height.
(ii) Change your dog's water every day and clean his bowl a few times a week to minimize bacteria. Give your dog the right amount of water every day.
(iii) Try to lower your dog's weight. If your dog has kidney stones, it may be hard to keep the weight down.
(iv) Avoid water with added electrolytes, which can lead to kidney stones. Your dog's water bowls are one place that should never be refilled since their surfaces can be contaminated.Choose from options above and answer: What most naturally follows?

How to prevent kidney stones in dogs
Make sure that your dog always has access to fresh, clean water.
Water helps to dilute your dog's urine, which keeps the minerals in the urine suspended in fluid. Drinking enough water also makes your dog urinate on a regular schedule, which helps to flush the minerals in the urine from your dog's body.
Answer:
(ii)