A binary search tree contains the numbers 1, 2, 3, 4, 5, 6, 7, 8. The tree is traversed in pre-order and the values of in each node printed out the sequence of values obtained is 5,3,1,2,4,6,8,7. If the tree is traversed in post order, the sequence obtained would be
A) 8 7 6 5 4 3 2 1
B) 1 2 3 4 8 7 6 5
C) 2 1 4 3 6 7 8 5
D) 2 1 4 3 7 8 6 5