The answer is 'by not fulfilling expectations'. The other options don't really surprise the reader, and if the plot is going into one direction, and then what you'd expect to happen doesn't actually happen, you are surprised, and the element of irony is achieved. 
        
                    
             
        
        
        
You should begin with a chart that separates both similarities and differences. Read both articles and annotate everything you notice on to the chart. You could then begin drafting all your work and revise.
        
                    
             
        
        
        
Answer: Imagines
Explanation: This funerary context for portrait sculpture was rooted in the longstanding tradition of the display of wax portrait masks, called imagenes, in funeral processions of the upper classes to commemorate their distinguished ancestry.