What is a metallic bonding?

A. The chemical bonding that takes place between metal atoms when they share electrons.
B. The chemical bonding that takes place from the attraction of metal atoms and the other elements.
C. The chemical bonding that takes place between metal atoms when they transfer electrons.
D. The chemical bonding that takes place from the attraction of positive ions and delocalized electrons.

D. The chemical bonding that takes place from the attraction of positive ions and delocalized electrons.