Removing first 2 drop down values from values prompt

1-Give a suitable name to your prompt.

In this case prompt name is:Prompt1

2-Place a html item after prompt.

3-paste following javascript.

<script language="javascript">
var f = getFormWarpRequest();
var list = f._oLstChoicesPrompt1;

list.remove(1);
list.remove(0);
list.removeAttribute("hasLabel");
list.options[0].selected = true;

canSubmitPrompt();
</script>