The theory that states “pieces of the Earth’s crust are in constant, slow motion driven by movement in the mantle” is called

Explanation

The theory states that pieces (plates) of the Earth’s crust keep moving slowly due to mantle motion is the Plate Tectonics Theory. According to this theory, the Earth’s crust is divided into many small and large plates. These tectonic plates move independently in different directions over the asthenosphere. The various landforms produced due to these plate movements are studied under plate tectonics.