What can I change so that I will get a list of only the first row?
i.e 

```
0 1
1 2
2 3
3 4

```

I have tried the below:

```
matrix = [[1, 2, 3, 4],
    [3, 5, 7, 9],
    [4, 6, 8, 10],
    [5, 7, 9, 11]]
for index in range(len(matrix)):
    print(index,matrix[index][0])

0 1
1 3
2 4
3 5

```