One of my client faced issue with Autor drop down which is in Admin section.
Display the authors in dropdown menu using hooks.
While creating the New post there was problem with the Author field. There are hundreds of irrelevant selections (users) and it’s difficult to select the right one.
WordPress is by default showing all the users in author drop down. I don’t want to show the other users in author drop down.
I searched for wp_dropdown_users hook or filter. But I did not found any proper solution.
Following articles are found helpful to me.
http://wordpress.org/support/topic/filter-for-post-quick-edit-author-drop-down
http://codex.wordpress.org/Function_Reference/wp_dropdown_users
Using that code I modified the code and I am able to fix the issue. You can put following code in to functions.php file.