{{B}}sEt 2 gEology plAtE tECtoniCs{{/B}}

why Do EArthquAkEs AnD volCAnoEs oCCur At plAtE BounDAriEsA．plAtE BounDAriEs unDErgo muCh tEnsion AnD FriCtion.
B．tEmpErAturEs FluCtuAtE grEAtly At plAtE BounDAriEs.
C．EArthquAkEs AnD volCAnoEs CAusE nEw plAtEs to Form.
D．thE CAusEs oF EArthquAkEs AnD volCAnoEs ArE unknown.