You can access the panel a button was present in using the Parent property.
Firstly, give each panel an appropriate title in the component browser. Let's assume you have a panel called 'Panel One'.
In the ButtonPushed callback for every button, add the following 3 lines
s = event.Source.Parent.Title; % s = 'Panel One'
k = strcat(s, ' is selected');
disp(k)
Now when you click on the button, 'Panel One is selected' will be rpinted out to the command window.
