Correct option**(d) polar ice**
Explanation:
Three fourth surface of earth (about 7 1 % of total) is occupied by oceans which contain 97.5% of total water. This is marine water with about 3.5% salt contents. Rest water, i.e. 2.5% is freshwater which occurs on land. Most amount of this water (about 1.97%) occurs as Frozen ice caps and glaciers and 0,5% fresh water occurs as groundv water.
