Answer:
B
Step-by-step explanation:
Binomials are expressions containing the sum (or difference) of two terms.
A. is not the answer because pq and qp are <u>products</u>.
C. is not the answer because 3x is not a sum/difference.
D. is not the answer because it is one binomial, not two muliplied together.
 
        
             
        
        
        
D is the answer 
(4+8)+1 = 13 
4+(8+1) = 13 
Therefore equation D is true