Which of the following letter-clusters will replace the question mark (?) in the given series? HFK, KHM, ?, QLQ, TNS

Which of the following letter-clusters will replace the question mark (?) in the given series? HFK, KHM, ?, QLQ, TNS

A.            NJO

B.            OKN

C.            MJN

D.            MKP

Sol:

Pattern follows here is: +3, +2, +2