ANSWER -
A convergent plate boundary is a type of plate boundary where two tectonic plates move towards each other and collide. When the leading edge of one plate dips beneath the other plate, it creates a subduction zone.
Volcanoes form at convergent plate boundaries because as the leading edge of the subducting plate sinks into the mantle, it melts and releases volcanic magma. This magma rises to the surface, where it can create a volcano. Volcanoes can form along the boundary where the two plates meet, or they can form on the overriding plate above the subduction zone. The type of volcano that forms depends on the types of rocks and minerals present in the magma and the characteristics of the subduction zone.