Question

The diagram below shows the layers in Earth's interior.

Diagram shows the internal layers of Earth. The central layer is labeled A and the layer surrounding A is labeled B.

Which of these statements best describes a difference between Layer A and Layer B?

Layer B is solid but layer A is molten.
Layer A is solid but layer B is molten.
Layer A moves in cyclic pattern but Layer B is stationary.
Layer B moves in cyclic pattern but Layer A is stationary.