Answer:
A. Iron.
Step-by-step explanation:
The Moon´s core is smaller in comparison with other terrestrial bodies. About 20% of the entire mass of it is the core.
The moon is composed of distinct crust, mantle, and core. While the crust is composed of freeze magma the core is believed to be formed by a mixture of metallic iron with a small amount of sulfur and nickel.
I hope this answer helps you.