Which letter-cluster from the options will replace the question mark (?) to complete the given series?
 ASDF, BUGJ, CWJN, ?

Which letter-cluster will replace the question mark (?) to complete the given series?

MDSA, KERC, ?, GGPG, EHOI

Which letter-cluster will replace the question mark (?) to complete the given series?

ABCD, FVJV, KPQN, PJXF, ?

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

ROM, URJ, XUG, AXD, ?

Which letter cluster will replace the question mark (?) to complete the given series?
 ETRE, AZJG, WFBI, SLTK, ?

Select the letter-cluster from among the given options that can replace the question mark (?) in the following series.
AAI, AEI, AII, AOI, ?

Which of the following numbers will replace the question mark (?) in the given series?
 4, 6, 12, 14, 28, 30, ?

Which letter-cluster will replace the question mark (?) to complete the given series?

REV, UXD, XQL, AJT, ?