JSP 中 HTML 下拉列表，默认显示已经选中过的值

<td style=" 300px">状态查询
<select name="status">
<option value="a" <c:if test="${status == 'a'}">selected</c:if>>请选择</option>
<option value ="b"<c:if test="${status == 'b'}">selected</c:if>>发送成功</option>
<option value="c"<c:if test="${status == 'c'}">selected</c:if>>等待发送</option>

</select>