If Gold Were Always Sold by Weight, Could You Make

If gold were always sold by weight, could you make money buying gold at one altitude above the ground and selling it at a different altitude?

A) Yes, you could make money by buying gold at a lower altitude and selling it at a higher altitude.
B) Yes, you could make money by buying gold at a higher altitude and selling it at a lower altitude.
C) Yes, you could make money by buying it at either a lower or higher altitude, and then selling it at the other altitude.
D) No, you couldn't make any money this way because the mass of the gold would be the same at both altitudes.
E) No, you couldn't make any money this way because the weight of the gold would be the same at both altitudes.