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

BJT, DHV, FFX, ?, JBB

HDZ

Explanation:

BJT, DHV, FFX, ?, JBB

The logic followed here is :

B → (-2) → D → (-2) → F → (-2) → H → (-2) → J

J → (-2) → H → (-2) → F → (-2) → D → (-2) → B

T → (+2) → V → (+2) → X → (+2) → Z → (+2) → B

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