Correct Answer - Option 4 : NPR
According to the positions of alphabets in English alphabet series.
Insert alphabet table :
The pattern followed here is:
1) KLM = K + 1 → L; L + 1 → M
2) PQR = P + 1 → Q; Q + 1 → R
3) BCD = B + 1 → C; C + 1 → D
4) NPR = N + 2 → P; P + 2 → R (Not followed the pattern)
Hence, 'NPR' is the correct answer.