Select the letter cluster that will replace the question mark (?) in the following series.
ACEGI, BDFHJ, KMOQS, ? , UWYAC, VXZBD
Answer & explanation
Correct answer: option 4
Explanation:

Explanation:
ACEGI, BDFHJ, KMOQS, ? , UWYAC, VXZBD
The logic followed here is :
A → (+1) → B → (+9) → K → (+1) → L → (+9) → U → (+1) → V
C → (+1) → D → (+9) → M → (+1) → N → (+9) → W → (+1) → X
E → (+1) → F → (+9) → O → (+1) → P → (+9) → Y → (+1) → Z
G → (+1) → H → (+9) → Q → (+1) → R → (+9) → A → (+1) → B
I → (+1) → J → (+9) → S → (+1) → T → (+9) → C → (+1) → D
So, the letter-cluster that replaces the (?) to complete the series is "LNPRT"