In the series first and second letters positional geometric sum and addition of third letters position ( If any ) leads to a series of numerical or number series which is represented as 13,14,15,16,17 so on . That means FBA's total value is (FXB)+A=(6X2)+1 , DCB's total value is (DXC)+B=(4X3)+2, so on . Hence correct answer is CEB ( (CXE)+B=(3X5)+2 =17 ) .
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