Which of the following letter-clusters will replace the question mark (?) in the given series?
 PK, GT, XC, OL, ?

Select the combination ofletters that when sequentially placed in the blanks of the given series will complete the series.
 dq_pln_qt_lnd_tpl_dq_p_n

From the given alternatives the word which cannot be formed using the letters of the given word
PSYCHOLOGY

Choose the correct alternative from the given ones that will complete the given sequence.
LXF, MTJ, NPN, OLR, ?

If it is possible to make a meaningful word of English together with the first, fifth and eighth letters of the word APTITUDES, how many total words can be made of this type? 

Which one set of letters when sequentially placed at the gaps in the given letter series shall complete it.
deb, ijg, nol ? xyv

In the following question, which one set of letters when sequentially placed at the gaps in the given letter series shall complete it?
P _ R _ O _ _ E _ R _ S _ _ _ R O S

Select the option that represents the letters that, when placed from left to right in the following blanks, will complete the letter-series.
 Q W _ R T Q _ F R _ Q W _ _ T _ _ H R T