The line that is written at the top of the script to write a Perl script using CGI.pm is . . . . . . . .

This question is about how to tell your Perl script to use the special tools in the CGI.pm library. This library is used to make web pages that can interact with the user, like online forms.
Here's what each option means:
* Option A: use this CGI - This isn't a correct way to use the CGI library.
* Option B: put CGI - This is also not a correct way to use the CGI library.
* Option C: use CGI - This is the correct way to tell your Perl script to use the CGI.pm library. It tells Perl to load the tools from that library.
* Option D: include CGI - This is another way to say "use CGI" and also works correctly. It is a bit less common, but still works.
So the answer is Option C: use CGI