Final answer:
The answer is true: Earth is differentiated into layers, including the dense iron-nickel core, the mantle, and the thin crust, with varying compositions and densities due to the process called differentiation.
Step-by-step explanation:
The statement that the Earth consists of spherical shells with different compositions and densities is true. Internally, Earth is differentiated into several layers, including the inner and outer cores, the mantle, and the crust. The core is primarily composed of iron and nickel, with the inner core being solid due to immense pressure, while the outer core is liquid and generates Earth's magnetic field. Surrounding the core is the mantle, which consists of silicate minerals that are solid yet plastic in behavior. Finally, the crust is the thin outermost layer that comes in two main types - continental and oceanic - differing in thickness, composition, and density. All these layers are the result of differentiation, a process where materials are sorted by density, suggesting that Earth was once molten, allowing denser materials to sink and form the core.