If given enough time a rift valley will form what ?

When the tensional forces are strong enough to cause the plate to split apart, a center block drops between the two blocks at its flanks, forming a graben. The drop of the center creates the nearly parallel steeply dipping walls of a rift valley when it is new

answer; i believe that the correct answer to this statement is (exoticism); //

exoticism was a trend where musicians created music based on a far off foreign

not sure if this is what you'r looking for eubacteria and archaebacteria