A digital ____ is an electronic, encrypted, and secure stamp of authentication on a document.

The ________ paste option pastes a range of cells to a new range of cells with columns and rows switched

Fill in the blank(s) with correct word

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

``` 1 #include 2 using namespace std; 3 void showDub(int); 4 int main() 5 { 6 int x = 2; 7 showDub(x); 8 cout << x << endl; 9 return 0; 10 } 11 void showDub(int num) 12 { 13 cout << (num * 2) << endl; 14 } ``` a. line 3 b. line 4 c. line 7 d. line 11