TypeError: Error #1010: A term is undefined and has no properties

1

I’m having a tough year so far. Why do I get this error? The red text is the line with the error.


//I use this emptyContainer to easily clear objects at certain times (between questions, etc)
if(!Boolean(this.getChildByName('emptyMC')))
{
 var emptyContainer:MovieClip = new MovieClip();
 emptyContainer.name = "emptyMC";
 this.addChild(emptyContainer);
}



var remainder:int = 0; //This remainder is used to toggle the x setting from side to side.
 if(!charCountTest) //If the answer character count is less than 190, use narrow buttons.
 {
  mcQuestBack.height = 225;
  for(var i:int = 0; i < xmlFile.questions.question[questIndex].answers.answer.length(); i++)
  {
   remainder = i % 2;
   var ansBacking:btnAnsBack = new btnAnsBack();
   ansBacking.width = 363;
   ansBacking.x = mcQuestBack.x + ((ansBacking.width + 8) * remainder);
   if(i <= 1)
   {
    ansBacking.y = mcQuestBack.y + mcQuestBack.height + 8;
   }
   else if(i > 1 && i < 4)
   {
    ansBacking.y = mcQuestBack.y + mcQuestBack.height + 8 + 105;
   }
   else if(i >= 4)
   {
    ansBacking.y = mcQuestBack.y + mcQuestBack.height + 8 + 210;
   }
   
   ansBacking.buttonMode = true;
   ansBacking.label = xmlFile.questions.question[questIndex].answers.answer*.content;
   ansBacking.addEventListener(MouseEvent.CLICK, handleChoice);
   emptyContainer.addChild(ansBacking);
   emptyContainer.setChildIndex(ansBacking,0);
 
   if(xmlFile.questions.question[questIndex].answers.answer*.@correct == true)
   {
    correctAns = xmlFile.questions.question[questIndex].answers.answer*.content;
   }
 
   var choiceText:TextField = new TextField();
   choiceText.defaultTextFormat=formatWhite;
   choiceText.multiline=true;
   choiceText.selectable=false;
   choiceText.mouseEnabled = false;
   choiceText.wordWrap=true;
   choiceText.border=false;
   choiceText.width=330;
   choiceText.autoSize=TextFieldAutoSize.LEFT;
   choiceText.text = xmlFile.questions.question[questIndex].answers.answer*.content;
   //choiceText.y = ansBacking.y + (30 * (26/choiceText.height));
   //choiceText.x = ansBacking.x + (ansBacking.width/2) - (choiceText.text.length * 3.3);
   [COLOR=#FF0000]emptyContainer.ansBacking.addChild(choiceText);[/COLOR]
  }
 }