What should come in place of the question mark (?) in the given series based on the English alphabetical order? ZYB, GFI, NMP, UTW, ?

Complete the series by choosing the correct option: EF, IJ, MN, _____

What should come in place of the question mark (?) in the given series based on the English alphabetical order? GSE LVZ QYU VBP ?

What should come in place of the question mark (?) in the given series based on the English alphabetical order? ELX, DJU, ?, BFO