how to add role based security using (ul - li) for menus ?

Hi, All
   How can I implement role based security that would show the admin tab if the user was logged in as a admin by using (ul-li) like the below code as a simple example. I do not want to use the menu control is this possible ?
 
  <ul>
<li><a href="#">Services</a></li>
<li><a href="#">About us</a></li>
<li><a href="#">Admin</a></li>
</ul>
Many Thanks
Kered

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