Water evaporates from the ocean and land surfaces, is held temporarily as vapour in the atmosphere, and falls back to Earth's surface as precipitation. ... Water that infiltrates Earth's surface becomes groundwater, slowly seeping downward into extensive layers of porous soil and rock called aquifers.
The problems that will receive priority are the physiological needs such as air, food and water.
Maslow's hierarchy of needs is a theory in psychology which organizes people's needs according to their priorities. It is represented as a pyramid with five steps which include: physiological(at the base), safety, belongingness, esteem and self actualization.
The physiological needs at the base of the pyramid are the first priorities.
rain or thunderstorms
typically thunderclouds and storms are the post affect of a cold front, causing D to be your answer, MrKnowledge