So try and recognize the pattern. For level 1, you have 1 box and 12 cans. In 2, you have 3 boxes and 36 cans. 12/1 is 12, 36/3 is 12 and so on. The # of boxes times 12 is the number of cans. The # of boxes in the display is equal to the total number of boxes in each level. Level 5 will mean 1+2+3+4+5=15. Level 6 is 1+2+3+4+5+6=21. So if 6 has 21 display boxes, we can do 21*12 and you will get 252. Your answer is E, 252 cans.