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What supplies the power that keeps Earth's crustal plates moving?
ASteady pull of lunar gravity
BDaily spin of Earth's crust
CWind blowing across oceans
DSlow convection in the mantle
Answer & Solution
Correct answer: D. Slow convection in the mantle
1. Heat built up inside the planet has to escape towards the surface.
2. Warmer mantle material rises and cooler material sinks, which is convection.
3. That slow churning drags the plates along above it.
4. Lunar gravity raises tides in the ocean but does not drive the plates.
_Source: OpenStax Astronomy (CC BY 4.0), section 8.2 Earth’s Crust_
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