Are underground areas that have the ability to contain and provide water sources.
a. shamals
b. wadis
c. seas
d. aquifers

The answer is D. There are different types of aquifers (such as the unconfined and confined aquifers), however, they are all made up of permeable rock that holds underground water. The aquifer could be sandwiched between impermeable rocks called aquitard that restrict the movement of the water in the aquifer. This type is called a confined aquifer.

landlessness of ordinary people

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