The correct use of comparative is found in the following sentence: 
<span>D. George has a bigger appetite than Harry.
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Below, I will correct the other sentences:
A. This is the worst picture I've ever seen.
B. Alicia is a better swimmer than Marilynn.
<span>C. Of the three girls, Janet is the best speaker.</span>
        
             
        
        
        
 All these<span> poems are written in </span>decasyllabic<span> rhymed verse, with varied arrangement of the rhymes. An Introduction to the Study of Browning. Arthur Symons. The </span>decasyllabic line<span> was an old measure; so was the seven-</span>line<span> stanza, both in Provençal and French. Medieval English Literature William Paton Ker. The whole ten ...</span>
        
             
        
        
        
<span>He repeatedly hints that he is too old to properly host</span>
        
                    
             
        
        
        
Explanation:
 Ok so did you not read the story? 
 
        
             
        
        
        
1 and 2 are the correct answers