Drop down list code for sidebar

Well, in a “layman’s” terms, you need to add your preferred filter (specific category id and order) to the $args array, like so:

$args = array( 
    'numberposts' => '5', 
    'post_status' => 'publish', 
    'cat' => 5, 
    'order' => 'ASC',
    'orderby' => 'title'
);

The 'cat' should be the id of the “specific” category you want to show.

Hope that helps.