In following questions, one term in number series is incorrect. - Find out the incorrect number 11, 2, 21, 3, 32, 4, 41, 5, 51, 6

Answer: C. 32

The given sequence is a combination of two series :
I.   11, 21, 32, 41, 51   and
II.   2, 3, 4, 5, 6.
Clearly, the pattern in I is + 10.
So, 32 is wrong and should be replaced by (21 + 10)  i.e. 31