Ireally need its so easy but i don't understand the question because i am not good at reading english, ?

imagine you are drilling to the center of the earth. order the layers as you would encounter them, from the outside in.

crust, upper mantle, lower mantle, outer core, inner core
crust, lower mantle, upper mantle, inner core, outer core
inner core, outer core, lower mantle, upper mantle, crust
upper mantle, lower mantle, outer core, inner core, crust