Select the c ombination of letters that when sequentially placed in the blanks of the given series will complete the series.
 _ c _ d d _ c a _ c b d d b _ a

The series given below contains a sequence of numbers. Identify the incorrect combination.
5, 6, 7, 8, 10, 11, 13, 15, 19

Which of the following letter-clusters will replace the question mark (?) and complete the following letter-cluster series?
 DW, FU, GT, IR, JQ, ?

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

AYD, BVF, DRH, ?, KGL

In the given word ‘MOTIVATION’ if the vowels are changed to the next letters and the consonants are changed to the previous letters as per the alphabetical series, then which letter/letters are repeated more than once?

Select the option that represents the letters that, when sequentially placed from left to right in the blanks below, will complete the letter series.
 _ M o N _ _ _ o M _ _ o _ _o M _ N o J o

Which letter cluster will replace the question mark (?) to complete the given series?
 WFBI, UCWB, SZRU, ?

Which one set of letters when sequentially placed at the gaps in the given letter series shall complete it?
 _bc_ca_aba_c_ca