Select the option that represents the letters that, when sequentially placed from left to right in the blanks below, will complete the letter series.
BUP_ESH_UPL_SHB_PLES_BU_LE_H

Find the missing term: AZY, BXW, CVU, DTS, ?, FPO.

The given series is a letter cluster series with one term missing. Choose the correct option in place of the question mark and complete the series.
CBDA, GFHE, KJLI, ONPM, SRTQ,?

What should come in place of the question mark (?) in the given series based on the English alphabetical order?
XZR, UWO, RTL, OQI, ?