the given options that can replace the question mark (?) in the following series: ACE , BDF, CEG,?

First letters: A → B → C → D (each increases by 1)
Second letters: C → D → E → F (each increases by 1)
Third letters: E → F → G → H (each increases by 1)

Select the letter – cluster from among the given options that can replace the question mark (?) in the following series:
दिए गए विकल्पों में से उस अक्षर – समूह का चयन कीजिए जो निम्नलिखित श्रृंखला में प्रश्नवाचक चिह्न (?) के स्थान पर आ सकता है:
ACE , BDF, CEG,?

DFH DEH DFI DEI