Answer:
C
Explanation:
The presence of mobile electrons explains the reason why there is conduction of electricity in the solid state. Electrons are the part of atoms that are majorly responsible for the different characteristics that substances exhibit.
A good example of the conduction of electricity can be seen in the case of 2 crystalline forms of carbon. While one of the allotropes could conduct electricity, the other allotrope cannot conduct electricity.
The two allotropes we are talking about here is graphite and diamond. While graphite could be used in a whole lot of electrolysis set up as an electrode, diamond does not found use in cases like this despite its crystalline structure. The reason for this is simple.
While diamond does not contain free mobile electron in its molecule, these free mobile electrons are present in a molecule of graphite. These free mobile electrons are the main reason why graphite can conduct electricity and diamond cannot even though they are both crystalline forms of carbon.
