anchor.diff:          return '';
         };
       </pre>
  -    Here <em>return_url</em> is the url of the tool consumer to which result
  -    has to be returned. <em>urlParams</em> contains the launch url of the
  +    Here <em>return_url</em> is the URL of the tool consumer to which result
  +    has to be returned. <em>urlParams</em> contains the launch URL of the
       exercise, that tool consumer will add in the Submission Tool URL. <br><br>
   
       Once Submission Tool URL is added, instructors can publish the exercise to
  
positive.code:     <p>
        Previously we have described <%= link_to "here", lti_opendsa_path %> how
        OpenDSA implements LTI when a student tries to access an OpenDSA exercise
        from within an LTI tool consumer such as Canvas or Moodle. Here we
        explain how OpenDSA makes use of LTI to support an instructor who wishes
        to add individual OpenDSA visualizations or exercises to their course. To
        better understand this example, you should first try out the instructions
        that instructors will use to incorporate such materials into their
  
negative.code:       lti_instructions_opendsa_moodle_path %>.
      </p>
  
      LTI controller <em>(apps/controllers/lti_controller.rb)</em> in OpenDSA
      takes care of all the requests related to LTI. An LTI-compliant LMS expects
      a Tool Provider to open in an iframe. Therefore, at the start of the LTI
      controller, OpenDSA allows both the launch and the resource endpoints to
      open in an iframe.<br><br>
      <pre>
        after_action :allow_iframe, only: [:launch, :resource]
  