The picture is a gneiss rock. This is actually a kind of metamorphic rock, so that could also be the correct answer, but so could sedimentary or igneous rocks. This is because a gneiss rock is a sedimentary or igneous rock that has gone through the metamorphic process to become a different kind of rock. The best way to tell if a rock is a gneiss rock is to look for the light and dark bands.
They alternate and go light, dark, light, dark, light, dark, and so on and so forth. The catch here is that the sedimentary or igneous rock has to be there before it can go through the metamorphic process. Otherwise, the gneiss rock cannot be formed.