Carbon, silicon and germanium have four valence electrons each. At room temperature which one of the following statements is most appropriate?

A

The number of free conduction electrons is significant in C but small in Si and Ge.

B

The number of free conduction electrons is negligibly small in all the three.

C

The number of free electrons for conduction is significant in all the three.

D

The number of free electrons for conduction is significant only in Si and Ge but small in C.