The main layers of the Earth in correct order, from the surface moving down, are:

A) upper crust, outer core, inner core, mantle
B) outer core, inner core, upper mantle, lower crust
C) crust, mantle, outer core, inner core
D) upper mantle, lower mantle, inner core, crust

Earth's Layers

The division of the Earth into distinct layers including the crust, mantle, and core, each with its own properties and composition.

Surface

The outermost or uppermost layer of an object or area which is in direct contact with the environment.

Upper Mantle

The upper mantle refers to the portion of the Earth's mantle that lies just beneath the crust and extends to depths of about 660 kilometers, involved in tectonic processes.