Which letter cluster will replace the question mark (?) to complete the given series?
PFBR, MKUA, ?, GUGS, DZZB
1
HKPE
2
JPNJ
3
JLEJ
4
QYGC
Which letter cluster will replace the question mark (?) to complete the given series?
PFBR, MKUA, ?, GUGS, DZZB