The Band Structure of Semiconductors Differs from That of Metal

The band structure of semiconductors differs from that of metal conductors in that ________

A) metal bands are relatively empty, while semiconductor bands are nearly full.
B) metal bands are nearly full, while semiconductor bands are relatively empty.
C) metal conduction bands are lower in energy than valence bands, while semiconductor conduction bands are higher in energy than valence bands.
D) metal conduction bands are higher in energy than valence bands, while semiconductor conduction bands are lower in energy than valence bands.
E) valence bands in metals are either partially empty or overlap with conduction bands, while these bands in semiconductors are separated by a small gap.