Help!!! please!! this test is timed!! I will give brainliest!!!
What is a system?
2 points
The solid rock part of Earth, including mountains, valleys, continents, and all of the rock beneath the oceans
The set of all water on the earth's surface, such as lakes, seas, and oceans
A group of related parts that all work together to perform a specific function
The greenhouse gases that help keep the earth at a temperature where water is in liquid form