Question

Under or non-availability of usable water is called:
(A) Purification of water.
(B) Pollution of water.
(C) Rationing of water.
(D) Scarcity of water.

Answer 1

Hint: Water is an important natural resource as it is useful for every important work and it is also vital for every living organism for its survival. Not all water is useful for drinking purposes because water quality depends on its distribution.

Complete step by step solution:
On the earth’s surface, $ 71% $ is covered by water and the remaining land surface. Out of $ 71% $ water nearly $ 1% $ water is freshwater, $ 96.5% $ water is present in oceans, seas, and bays which is saline in nature, $ 1.74% $ water is present in frozen form and remains are groundwater. Due to the presence of less freshwater which can be used for daily purpose, there is always a shortage of water. Shortage of water is also increased from time to time due to an increase in water pollution and water wastage. Out of $ 1% $ freshwaters for humans, $ 70% $ of the freshwater is used for agriculture purposes, and the remaining $ 30% $ is potable water.
Water pollution degrades the quality of water due to the presence of impurities. There are two sources of water pollution, one is natural and one is manmade. Natural water pollution caused by soil erosion and leaching whereas man made water pollution caused by industrial effluents, domestic sewage, animal waste, fertilizers, etc. Water pollution leads to the extinction of aquatic species and it also harms animals and human beings. Water treatment and proper disposal of liquid waste help to decrease water pollution.
Scarcity of water is the under or non-availability of usable water. This water presence in the ground is very less and this may sometimes lead to draughts.
Therefore, the correct answer is option D i.e. under or non-availability of usable water is called scarcity of water.

Note:
Water crises also increase with environmental change because it leads to the condition of drought and lack of rainfall. Due to this two-third of people live under the condition of water scarcity which is equal to more than two people in every six people who do not get proper portable water.