Answer: 1%
As per excerpts, Water covers 75 percent of Earth and 97 percent of water on Earth is salt water, meaning only 3 percent of water is available as fresh water. Based on this information, 3% of 75% of the water on earth is available as fresh water or 2.25%. Since most of the water is said to be locked up in solid glaciers and polar ice caps, the amount of water on the planet that is available for animals to drink is lesser than 2.25% so the best approximation is 1 percent.