In this case, we'll have to carry out several steps to find the solution.
Step 01:
Data
data set
center = ?
Step 02:
We must analyze the data sets to find the solution.
Data set A: 2, 3, 1, 4, 2, 0 , 0 ===> 4
Data set B: 6 , 4, 5, 6, 5, 7, 8, 7 ===> 6
Data set C: 1, 4, 0, 2, 4, 4, 6, 7 ===> 2
Data set D: 7, 8, 10, 11, 8, 9, 10, 9, 11 ===> 9
That is the full solution.