What kind of vehicle is the truck in front of?
The truck is in front of the cars.
    src        edge_attr  dst
0     0  to the right of    2
1     0   to the left of    1
2     0  to the right of   11
3     1  to the right of    7
4     1  to the right of    3
5     1   to the left of   10
6     1      in front of    3
7     1  to the right of    0
8     2   to the left of    0
9     2   to the left of   11
10    2  to the right of    9
11    3           behind    1
12    3           behind    7
13    3   to the left of    1
14    3   to the left of   10
15    4   to the left of   10
16    5  to the right of    6
17    6   to the left of    5
18    7   to the left of    1
19    7      in front of    3
20    9   to the left of   11
21    9   to the left of    2
22   10  to the right of    3
23   10  to the right of    1
24   10  to the right of    4
25   11   to the left of    0
26   11  to the right of    2
27   11  to the right of    9