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

Correct option is D

AKRW, DNUZ GQXC, ?
First letter + 3 (in each of the terms)
Second letter + 3 (“)
Third letter + 3 (“)
Fourth letter + 3 (“)
G – (+3) = J
Similarly, Q – T, X – A and C – F
? = JTAF