Answer:
The folded mountains are formed when two plates share a convergent plate boundary. These are the region where the plates are subjected to compressional stress from both sides.
The Andes mountain is an example of the folded mountains that are formed due to the convergent of Nazca and the South American plate. It forms the longest mountain range in the world extending from the northwestern to the Southwestern side of South America through the west.
As the plates converge, the heavier plate subducts and melts at great depth and after mixing up with the magma, it again rises up due to the force exerted by the convection current. It then rises up towards the over-riding plate, giving rise to the formation of volcanoes and volcanic arcs.