What will the following code display?

```
#include
using namespace std;
void doSomething(int);
int main()
{
int x = 2;
cout << x << endl;
doSomething(x);
cout << x << endl;
return 0;
}
void doSomething(int num)
{
num = 0;
cout << num << endl;
}
```

a. 2
0
2
b. 2
2
2
c. 0
0
0
d. 2
0
0

a. 2
0
2