单选题：Given the adjacency list of a directed graph,

Given the adjacency list of a directed graph,
```
0: 4,5,6
1: Empty
2: Empty
3: 1,2
4: Empty
5: 3
6: 2
```
which one below is NOT a valid topological order of the graph?
@[C](3)

A. `0, 4, 5, 3, 1, 6, 2`
B. `0, 5, 4, 3, 6, 1, 2`
C. `0, 4, 6, 2, 5, 3, 1`
D. `0, 6, 5, 4, 3, 2, 1`



A.`0, 4, 5, 3, 1, 6, 2`
B.`0, 5, 4, 3, 6, 1, 2`
C.`0, 4, 6, 2, 5, 3, 1`
D.`0, 6, 5, 4, 3, 2, 1`


答案：C