A word-based series is given with a blank in it. Read the series carefully and find which of the following element is suitable for the blank in series?

CDB HIG MNL ____ WXV

What will come in place of question mark (?) in the following series

BDF, ?, PRT, WYA

This question is based on the following words.
PAD SHE NOT WIN
If in each of the words, each letter is changed to the next letter in the English alphabetical order, how many words thus
formed will have no vowel?