The theory of plate tectonics describes the movement of the lithosphere floating atop which of Earth's layers?
a. Asthenosphere
b. Inner core
c. Outer core
d. Lower mantle
e. Crust
Question 2The combined ideas of continental drift and seafloor spreading led to which overriding concept?
a. Convection currents
b. Plate tectonics
c. Subduction zones
d. Isostasy
e. Conduction currents