Which best explains why all of the Earth’s freshwater is not available for human use?

2.5% of the earth's fresh water is unavailable: locked up in glaciers, polar ice caps, atmosphere, and soil; highly polluted; or lies too far under the earth's surface to be extracted at an affordable cost.

Explanation:

99% of liquid freshwater on Earth is Stored as Ground water

Much of it probably isn't accessible to us Human.

About 71 % of Earth is covered in water, and the Ocean holds most of it but this is salt water, almost all fresh water is stored underground

x would be the most and the least would be y because there are more fruit   and seeds than flock z has insects

option c is the correct answer.