Suppose It Is Proposed That Some of Earth's Crust Might

Suppose it is proposed that some of Earth's crust might be leftover solid material from the planetesimals that collided to form the planet. What do you think of this idea? Three of the following are reasonable responses to this idea. Which one is not?

A) This is quite possible, because the age of the planetesimals is about 4.5 billion years-the same as the age of Earth.
B) This is not possible, because radioactive decay, among other sources, melted Earth soon after its formation, and the resulting chemical differentiation would have destroyed any original solid crust.
C) This is not possible, because the original impact energy of the planetesimals plus the energy of subsequent impacts, among other sources, melted Earth soon after its formation, and the resulting chemical differentiation would have destroyed any original solid crust.
D) This is not possible, because geologic activity has resurfaced Earth since its formation, leaving no trace of the original solid crust.