Select the letter Cluster that can replace the question mark (?) in the following series.
QKR, UOV, YSZ, CWD, ?
Answer & explanation
Correct answer: option 1

Explanation:
QKR, UOV, YSZ, CWD, ?
The logic followed here is :
Q → (+4) → U → (+4) → Y → (+4) → C → (+4) → G
K → (+4) → O → (+4) → S → (+4) → W → (+4) → A
R → (+4) → V → (+4) → Z → (+4) → D → (+4) → H
So, the letter-cluster that replaces the (?) to complete the series is "GAH"