title: Add new <option> to all dropdown <select> tags using javascript
body: <p>Im trying to add a Drop down menu option "Please select" to the top of each drop-down list on a page to be selected by default, using something similar like this:</p>
  
  <pre><code>window.onload = function() {
      $('select option[value="PSC"]').attr("selected",true);
  };
  </code></pre>
  
  <p>and this is what im using for the drop-down:</p>
  
  <pre><code>window.onload = function AddItem(text,value) {
      // Create an Option object
      var opt = document.createElement("option");
      // Add an Option object to Drop Down/List Box
      document.getElementsByTagName("option").options.add(opt);
      // Assign text and value to Option object
      opt.text = 'Please select...';
      opt.value = 'Please Select';  
  }
  </code></pre>
  
  <p>I'm new at javascript, can someone point me in the right direction to compiling this together so that when the page loads every drop-down list gets a default selected option called "Please select"</p>
  
  <p>Thanks in Advance</p>