The study of the location of fracture zones has provided evidence to support the theory of plate tectonics because a. fracture zones indicate the locations of once-active underwater faults. b. fracture zones prevent subduction at ocean trenches. c. fracture zones allow old, oceanic crust to be subducted by continental crust. d. fracture zones indicate that tectonic plates are always stationary.

 fracture zones allow old, oceanic crust to be subducted by continental crust. 

The study of the location of fracture zones has provided evidence to support the theory of plate tectonics because fracture zones are the zones where new oceanic crust is formed, allowing old oceanic crust to be subducted by continental crust, thus creating a circle in the crust that is a piece of evidence in support of the theory of plate tectonics. 

Brand c i think that should be it

Answera discharge of static electricity;