Against Which Variable Force Must Work Be Done to Raise

Against which variable force must work be done to raise mountains?

A) the rigidity and tensile strength of the rock, which varies with rock type
B) gravitational pull, which varies with distance from Earth's core
C) the attractive force of the mantle and the melting and subduction of the Earth's crust at boundary zones, which varies according to plate speed
D) the magnetic attraction of Earth's core, which will vary according to the composition of the rock in the mountains being pushed up