The Terrestrial Planet Cores Contain Mostly Metal Because

The terrestrial planet cores contain mostly metal because

A) metals sank to the center during a time when the interiors were molten throughout.
B) metals condensed first in the solar nebula and the rocks then accreted around them.
C) the entire planets are made mostly of metal.
D) convection carried the metals to the core.
E) radioactivity created metals in the core from the decay of uranium.