If m is a 7 ? 7 integer matrix, what is displayed by this code fragment?

```
for ( int i = 0; i < 7; ++i )
cout << m[3][i];
cout << endl;
```

a. The first three rows of m.
b. The first three columns of m.
c. The middle row of m.
d. The middle column of m.

c. The middle row of m.