Final answer:
The oceanic crust is the layer of the Earth's interior composed of basalt.
Step-by-step explanation:
The layer of the Earth's interior that is composed of the volcanic rock basalt is the oceanic crust. The oceanic crust is the outermost layer of the Earth's lithosphere and is found beneath the ocean basins. It is thinner and denser than the continental crust, which is made up of granite.
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