What is the continuous process by which water moves from Earth's surface to the atmosphere and back?

• A. transpiration
• B. water cycle
• C. precipitation
• D. surface run-off

Answer: (B)

The water cycle is the continuous movement of water through Earth’s surface and atmosphere. It starts with evaporation from oceans, lakes, and rivers, driven by heat from the sun, and includes transpiration from plants. The water vapor rises, cools, and condenses into clouds, which release precipitation like rain or snow back to the surface. From there, water can run off across the land, soak into the soil to replenish groundwater, or flow back into bodies of water, continuing the cycle. While transpiration, precipitation, and surface run-off are all parts of this process, they describe only pieces of the cycle; the water cycle as a whole encompasses all these steps in a single, ongoing system.