What is a better approach to AlertDialog?

Let's put it this way; What is a better approach when you ask user to confirm/reject something while need to choose a value in a mobile application?

I have the following options:

1. Scroll-able content.
   • Just like what Google suggested in here.
2. predefined value in application Settings.
   • To set it before-hand by user.
3. etc..

edit: Accepted the answer because I needed more clarifications that actually happened to be in the first reply. In my approach I will need to present a large list to the user which should be placed in the Application Settings cause it is not a well-formed approach to put it in a pop up. Better solution for this case is point 3 in the accepted answer!

Thanks