Select the letter-clusters from among the given options that can sequentially replace both the question marks (?) in the following series.

ZCKR, bfow, DISB, flwg, HOAL, ?, ?

jreq, LUIV

Explanation:

ZCKR, bfow, DISB, flwg, HOAL, ?, ?

The logic followed here is :

Z → (+2) → b → (+2) → D → (+2) → f → (+2) → H → (+2) → j→ (+2) → L

C → (+3) → f → (+3) → I → (+3) → l → (+3) → O → (+3) → r → (+3) → U

K → (+4) → o → (+4) → S → (+4) → w → (+4) → A → (+4) → e → (+4) → I

R → (+5) → w → (+5) → B → (+5) → g → (+5) → L → (+5) → q → (+5) → V

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