Answer:
I believe A. $1.25 per box would be the best deal.
Step-by-step explanation:
This is because A is $1.25 per box,
B. is about $1.83 per box (5.50/3 divided by 3/3 = about 1.83/1)
C. Would be 1 box = $3.50, and the next $1.75 (which is still not less then just $1.25 per box)
and D. would be $2.75-$1 off = $1.75
Out of all of them, A is cheapest/gives the best deal.
Not sure if all calculations are correct, but I hope this helps! :)