Many of the islands of Indonesia (Java, Sumatra, Borneo), which are located adjacent to a subduction zone next to the edge of the continental shelf of SE Asia, consist of felsiclava. This means that the lava that produces these islands is derived from

A) a midocean ridge.

B) a volcanic hot spot under the ocean floor.

C) the melting of continental shelf material along with ocean floor material.

D) the melting of subducted plate material and nothing else.

E) a rift zone