What will come in place of the question mark (?) based upon the given seating arrangement : AF DG CA ?

G is sitting third to the right of F.

H is not an immediate neighbour of F and G. A is sitting second to the right of H, => H sits 2nd to the right of G and A sits to the immediate left of F.

B is sitting third to the right of C and C is not an immediate neighbour of G, => C sits to the immediate left of A and B sits to the immediate right of F.

D is not an immediate neighbour of H or C, => D sits between B and G, thus E sits between G and H.

Series : AF DG CA ?

1st person : A (+3 positions) = D (+4 positions) = C (+5 positions) = G

2nd person : F (+3 positions) = G (+4 positions) = A (+5 positions) = E

Thus, missing term = GE 

=> Ans - (C)