Correct option is B
Given series: ?, N, K, H, E, B
Logic: The series decreases by 3 at each step:
N = 14, K = 11, H = 8, E = 5, B = 2.
The pattern in the positions:
14 (N) → 11 (K) → 8 (H) → 5 (E) → 2 (B).
For the missing letter before N:
Add 3 to 14 (N) to get 17.
The 17th letter of the alphabet is Q.
Correct answer is (b) Q