Answer:
D. All of the Above 
Explanation:
i just took the test on edgenuity
 
        
             
        
        
        
The ground<span> state of an electron, the energy level it normally occupies, is the state of lowest energy for that electron. ... An electron </span>can become excited<span> if it is given extra energy, such as if it absorbs a photon, or packet of light, or collides with a nearby </span>atom<span> or particle. (I do not take credit for that answer)</span>
        
             
        
        
        
Answer:
Option D. Iron and sulfur react to form iron sulfide 
Explanation:
Reaction of iron with sulphur is a chemical property and not a physical property. 
 
        
             
        
        
        
It could be used as a buffer, since it is not a conductor.  Hope this helps!!!