What Do the Tube Worms of the Hydrothermal Vent Communities

What do the tube worms of the hydrothermal vent communities directly rely on for their survival?

A) direct chemical oxidation of sulphide minerals by their root-like, chitinous tube-feet
B) pelagic organic debris settling slowly from the sea surface and local decaying organic matter from crabs, clams, fish, and stupid marine biologists
C) photosynthesis from weak sunlight filtering down to the seafloor
D) symbiotic chemosynthetic (sulphur based) bacteria residing in their trophosomes (guts)