Select the letter-cluster from among the given options that can replace the question mark (?) in the following series.
EDC JIH ONM TSR ?
AYWX
BWYX
CYXW
DWXY
AYWX
BWYX
CYXW
DWXY
Related Questions:
What would come at the place of question mark in the number series ?
2 , 10 , 30 , 68 , ?