(i). Eleven students, A, B, C, D, E, F, G, H, I, J and K, are sitting in the first row of the class facing the teacher.
(ii). D who is to the immediate left of F is second to the right of C.
(iii). A is the second to the right of E, who is at one of the ends.
(iv). J is the immediate neighbour of A and B and third to the left of G.
(v). H is to the immediate left of D and third to the left of I.

If E and D, C and B, A and H and K and F interchange their positions, which of the following pairs of students is sitting at the ends ?

###### Option:
A. D and E
B. E and F
C. D and K
D. K and F
E. None of these
Answer: C . D and K

Justification:

D is to the left of F and second to the right of C i.e. C - D F.
A is second to the right of E i.e. E - A.
J is immediate neidhbour of A and B and third to the left of G i.e. A J B - G.
H is the left of D and third to the right of I i.e. I - H D.
The above four orders may be combined to obtain the correct order as under :
E, K, A, J, B, I, G, C, H, D, F

The new sequence formed on interchanging seats is :
D, F, H, J, C, I, G, B, A, E, K
D and K are sitting at the ends in the new arrangement.