Answer: D: Aquifers are layers of porous rock or sand.
Aquifers are layers of porous rock or sand.
Explanation:
Aquifers refer to underground layers of rock which are socked with water and can be brought to the surface by natural springs. It is layers of saturated rock through which water can easily move. Aquifers can be located at the ground surface or very deep underground where they cannot be accessed. They can also be very large. It can come in two forms which are confined and unconfined aquifers.