title: What is dirty update in asp.net mvc
body: <p>I want to know what will happen if I pass a query string parameter which will have the same name as a control on the form from view to controller?</p>
  
  <p>From where the controller will pick the value:
  A. From control ()
  B. From query string(?firstname=somename)</p>
  
  <p>Thanks in advance</p>