Correct Answer - Option 4 : 9
The logic followed here is,
(middle number) = diffterence of sum of digits of adjacent numbers
I → 5 + 2 + 6 = 13 & 9 + 5 + 7 = 21
Now 21 – 13 = 8,
II → 9 + 4 + 1 = 14 & 8 + 5 + 6 = 19
Now 19 – 14 = 5,
Similarly,
III → 2 + 5 + 1 = 8 & 6 + 8 + 3 = 17
Now 17 – 8 = 9,
Therefore, 9 is the correct answer.