Answer:
D. Yes, because the price is 5 times the number of boxes
Explanation:
To know if they are proportional check to see if there is a number common to the relationship between the y and x to all the numbers:
10/2=5
15/3=5
20/4=5
25/5=5
There is a relationship of 5 and the 5 is multiplied to the x=boxes.
So the correct answer is, Yes, because the price is 5 times the number of boxes.