title: dropdown option and action
body: <p>I have a drop down and inside that i have options. On clicking the option it must display fields respectively.
  Like for
  option1 == one text box
  option2 == two text box and so on...</p>
  
  <pre><code>&lt;select id="dropdown"&gt;
  
      &lt;option value="A"&gt;option1&lt;/option&gt;
      &lt;option value="B"&gt;option2&lt;/option&gt;
      &lt;option value="C"&gt;option3&lt;/option&gt;
      &lt;option value="D"&gt;option4&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p>on clicking option1 one field must be shown. on option2 two fields.. am new to javascript and html. Please help friends..</p>