Select the letter-cluster from among the given options that can replace the question mark (?) in the following series.

TALT, YAGT, YFGO, DFBO, DKBJ, ?

IKWJ

Explanation:

TALT, YAGT, YFGO, DFBO, DKBJ, ?

The logic followed here is :

T → (+5) → Y → (+5) → Y → (+5) → D → (+5) → D → (+5) → I

A → (0) → A → (0) → F → (0) → F → (0) → K → (0) → K

L → (-5) → G → (-5) → G → (-5) → B → (-5) → B → (-5) → W

T → (0) → T → (0) → O → (0) → O → (0) → J → (0) → J

So, the letter-cluster that replaces the (?) to complete the series is "IKWJ"