Why does every Caribbean island have its own volcano?

The Eastern Caribbean islands lie on a plate boundary. The North American Plate, which is the denser of the two, sinks beneath the Caribbean Plate creating suitable conditions for magma to be produced. The magma then rises to the surface of the Earth where it may erupt to form a volcano.

Explanation:

The reason why everg Caribbean island have their own volcano is because Eastern Caribbean islands they lie on what you would call is a plate boundary. Also the North American plate, Which basically is the denser of the two, sinking beanethe the Caribbean plate, which creates a suitable condition of magma that is produced. Magma then rises to the surface of the earth where it may erupt to form a Volcano.