Which box plot represents the data?
11 6 19 14 21 7 13 15 15
answer choices :

It would be the last one 

That is a good question

First:
order them

11 6 19 14 21 7 13 15 15

6    7    11  13  14  15  15    19    21

min=6
max=21
median=14

Q1=median of {6    7    11  13}
Q1=9

Q3=median of{15  15    19    21}
Q3=17

The graph satisfies these is the first plot..

I hope I helped you.