Answer:
C. The boatswain asks what Sebastion is doing on the deck.
 
        
                    
             
        
        
        
Yes it is a metaphor because he does not literally have a key to her heart. It is just figurative speaking.
        
             
        
        
        
<span>Peter:How do you "half expect" something? 
Lois:I don't know, it's just a turn of phrase. 
Peter:How do you turn a phrase?</span>
        
                    
             
        
        
        
I think the correct answer is A