Which line in the following program contains the prototype for the showDub function? 1 #include 2 using namespace std; 3 4 void showDub(int); 5 6 int main() 7 { 8 int x = 2; 9 10 showDub(x); 11 cout

Which line in the following program contains the prototype for the showDub function?

1 #include

2 using namespace std;

3

4 void showDub(int);

5

6 int main()

7 {

8     int x = 2;

9

            10     showDub(x);

            11     cout < x=""><>

            12     return 0;

            13 }

            14

            15 void showDub(int num)

            16 {

            17     cout < (num="" *="" 2)=""><>

            18 }