How do plate movements on Earth's crust create earthquakes and volcanic activity?

Plate movements on Earth's crust create earthquakes and volcanic activity through the process of tectonic activity. When tectonic plates shift and collide, they can create stress and pressure in the Earth's crust. This pressure can build up over time and eventually be released in the form of earthquakes or volcanic eruptions. The movement of plates can also cause magma to rise to the surface, leading to volcanic activity.