Answer:
Plz give me the text to summarize your A 
 
        
             
        
        
        
The sentence that uses the underlined word correctly is D) The school council used multiple media to advertise the prom.
The plural of medium is media, if you are referring to TV, or radio, etc.
Mediums are people who can speak to ghosts. 
        
             
        
        
        
It is C. Adverb. I'm not just gonna type this senctence so I can post the answer, as it'll be more than 20 characters.
        
                    
             
        
        
        
The answer is B. If we input the answer into the sentence it makes the most sense and it is more consistent in verb tense then the others. 
"Hassan is most productive when he has several hours at a time to focus on his work"<span />