What has caused the changes in the area of the Pacific Ring of Fire over thousands of years?

Directions: Read the passage carefully and answer the following question.

The Pacific Ring of Fire is the name that is given to a horseshoe shaped area in the Pacific Ocean which extends from South America and North America to Eastern Asia, Australia and New Zealand. This area is famous for its constant seismic activity and because of the amount of active volcanoes that can be found here. 75% of dormant and active volcanoes are found in the Pacific Ring of Fire. Now it is known that the area is very close to several tectonic plates which may be what influences the violent activity in the area. It is believed that the Pacific Ring of Fire has a total of 452 volcanoes. Some of the world’s most active volcanoes are found here. The volcanoes can be very dangerous to the population nearby. The Pacific Ring of Fire is different today than it was thousands of years ago because of the changes caused by tectonic plates. The Pacific Plate will hit other plates nearby and that causes them to sink. The crust melts producing the magma that feeds the different volcanoes in the Pacific Ring of Fire or it will help produce new volcanoes. The tectonic plates are the reason for the many violent earthquakes in the entire area of the pacific.