Need a custom code to place cursor in textbox when clicked on last option of the Matrix Question

Hi All,
We need a JS custom code to place the cursor in text box when clicked on last option of the Matrix question which is in the same page.
We have applied below code which works fine in the single scale question,
/*Place your JavaScript here to run when the page loads*/
  this.questionclick = function(event,element)
  {
    //by default you get the click event as the first parameter and the clicked element as the second parameter
    console.log(event, element);
    if (element.type == 'radio')
    {
     var inputText = $($(QID9)).down('.InputText');
    inputText.focus();
}
  }
It also works on Matrix question however page get scroll down each time we select a choice for the statements. Because of this we need to scroll up again for each statement to select the rating on this Matrix question which is kind of annoying to the person who takes the survey.
So we are trying to apply only when the choice of last statement of that Matrix question is selected.
Can anyone suggest on this or have any thoughts on how to resolve this?
Your response is much appreciated!