Question

Select the statement(s) that are accurate about plate tectonics and convection currents.


Convection currents in Earth's mantle cause Earth's plates to move.

Melted rock from the inner core moves toward Earth's crust because it is less dense.

Earth's plates move around on the upper mantle.

Plate tectonics is the theory that Earth's surface is broken into large land masses that move.

Molten rock cools as it nears Earth's crust and sinks back down toward the outer core.

Answer 1

Accurate:
- Convection currents in Earth's mantle cause Earth's plates to move.
- Earth's plates move around on the upper mantle.

Why the others are incorrect:
- "Melted rock from the inner core..." — False. The inner core is solid; molten material (the outer core) is metallic liquid, and mantle melt (magma) does not come from the inner core.
- "Plate tectonics is the theory that Earth's surface is broken into large land masses..." — Misleading. Plate tectonics says the lithosphere is broken into rigid plates (oceanic and continental) that move, not just "land masses."
- "Molten rock cools as it nears Earth's crust and sinks back down toward the outer core." — False/misleading. Cooled material near the surface can become denser and sink back into the mantle, but it cycles within the mantle (not specifically down to the outer core).