Which of the following reservoirs serves as a primary sink in the hydrologic cycle? Rocks and sediments Ice caps and groundwater The atmosphere The oceans

The primary sink in the hydrologic cycle is The oceans.

Here's why:

1. The hydrologic cycle, also known as the water cycle, describes the continuous movement of water on, above, and below the surface of the Earth.

2. The oceans cover about 71% of the Earth's surface and contain 97% of the Earth's water.

3. The cycle starts when water on the surface of the ocean heats up and turns into vapors, a process called evaporation.

4. The water vapor then cools down and becomes a liquid again, a process called condensation. This water falls back to the Earth's surface as precipitation.

5. Some of the water is taken up by plants and used in photosynthesis, some of it seeps into the ground and becomes part of the groundwater system, and some of it runs off into rivers and lakes and eventually back into the ocean.

6. Therefore, the ocean is the largest reservoir in the hydrologic cycle and serves as the primary sink.