22) A
Subtract the each cumulative percentage from the succeeding cumulative percentage.
3 or less = 4% (this should be on the graph for 3 or less)
6 or less = 15 – 4 = 11% (this should be on the graph for 6 or less)
9 or less = 39 – 15 = 14% (this should be on the graph for 9 or less)
12 or less = 60 – 39 = 21% (this should be on the graph for 12 or less)
15 or less = 79 – 60 = 19% (this should be on the graph for 15 or less)
18 or less = 91 – 79 = 12% (this should be on the graph for 18 or less)
This is only shown by graph A. So, A is the correct answer.