Analogy - Verbal and Reasoning

Directions to SolveIn each of the following questions find out the alternative which will replace the question mark.
Q1:

KeaC : CaeK :: XgmF : ?

A GmcF

B FmgX

C EgmX

D EmgF

ANS:B - FmgX

Explanation: First and fouth letters are interchanged while second and third letters are interchanged.