6 persons A, B, C, D, E and F are sitting around a rectangular table (not necessarily in the same order) facing towards the

centre. 4 persons are sitting at each corner, and one person is sitting at the middle of each shorter side of the table. B is an

immediate neighbour of D and C. F is an immediate neighbour of A and D. E is an immediate neighbour of A and C. F is not

sitting at any of the corners.

Which of the following pairs represents the persons who are sitting exactly opposite to each other?