How do volcanoes form at convergent boundaries?

-plates move towards each other
-denser plate sinks under the lighter plate (subduction)
-denser plate will melt because of the very high temperature in the inner core
-this magma will then rise up through cracks formed by the plates and then cools to form volcanoes

Ibelieve it is the 2nd answer, create gardens on all rooftops. let me know if this .

Answer sinking and cooled;