Select the letter-cluster from among the given options that can replace the question mark (?) in the following series.
OLK, MNL, KPM, IRN, ?
1
JQR
2
GTO
3
HSO
4
GUP
Select the letter-cluster from among the given options that can replace the question mark (?) in the following series.
OLK, MNL, KPM, IRN, ?