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

Question

( A ) The number of free electrons for conduction is significant only in Si and Ge but small in C
( B ) The number of free conduction electrons is significant in C but small in Si and Ge
( C ) The number of free conduction electrons is negligibly small in all the three
( D ) The number of free electrons for conduction is significant in all the three