What kind of vegetable is on the pizza?
The vegetable is a tomato.
    src        edge_attr  dst
0     0  to the right of   14
1     0  to the right of   15
2     0   to the left of    7
3     2  to the right of    6
4     3  to the right of   13
5     3             with    8
6     3  to the right of   10
7     3  to the right of   12
8     3        served on    4
9     3             with    1
10    6   to the left of    2
11    7  to the right of    8
12    7  to the right of    0
13    7  to the right of   14
14    8   to the left of    7
15    8               on    3
16    9   to the left of   11
17   10   to the left of    3
18   10               on    4
19   11               on    5
20   11  to the right of    9
21   12   to the left of    3
22   13   to the left of    3
23   14               on    3
24   14  to the right of   15
25   14   to the left of    0
26   14   to the left of    7
27   15   to the left of    0
28   15   to the left of   14