Code won't work on button?

hey all,

my code and listenersEvents won’t work on my button but when i put them in the frame they work?? why would this be??

here is my code:

var oListener:Object = new Object();
oListener.click = function(oEvent:Object):Void  {
    trace(oEvent.target.selectedData);
    //q2_answer = oEvent.target.selectedData;
    if(oEvent.target.selectedData == "A snail"){
    q2_answer = "Q1 is correct"
} else {
    q2_answer = "Q1 is incorrect"
}
};
q1.addEventListener("click", oListener);