Answer:
Vertically
Step-by-step explanation:
A fault is a rupture or fracture in the earth's crust (outer layer). The Earth's crust moves along these faults, in the case of reverse faults that movement occurs vertically, the earth on one side moves up and over the other side, I annexed an image to illustrate this motion. This kind of fault motion is caused by compressional forces and results in shortening.
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