Choose the missing terms out of the given alternatives.
AZ, BY, CX, DW, EV ?  Choose the correct answer:  A) EF  B) GH  C) ED  D) FU  E) KN
D   FU   The first letter moves one step forward. The second letter moves one step backward.
<result>D</result>
Choose the missing terms out of the given alternatives.
AZ, BY, CX, DW, EV ?