asp 在线考试多选题复选框怎么提交

<%if rs_tk("smallclassname")="多选题" then%>
<table width="85%" border="0" cellspacing="0" cellpadding="0">
  <tr>
    <td width="10" rowspan="2">&nbsp;</td>
    <td height="30" bgcolor="#CCCCCC"><br /><%=rs_tk("title")%>(&nbsp;)<br />&nbsp;</td>
  </tr>
  <tr>
    <td><br />
&nbsp;&nbsp;&nbsp;&nbsp;<input name="duoxuan<%=j%>" type="checkbox" value="A">A:<%=rs_tk("title1")%><br /><br />
&nbsp;&nbsp;&nbsp;&nbsp;<input name="duoxuan<%=j%>" type="checkbox" value="B">B:<%=rs_tk("title2")%><br /><br />
&nbsp;&nbsp;&nbsp;&nbsp;<input name="duoxuan<%=j%>" type="checkbox" value="C">C:<%=rs_tk("title3")%><br /><br />
&nbsp;&nbsp;&nbsp;&nbsp;<input name="duoxuan<%=j%>" type="checkbox" value="D">D:<%=rs_tk("title4")%><BR><br />
</td>
  </tr>
</table>
<%end if%>

复选框怎么提交,才能让多选的答案合并到一起赋值给duoxuan<%=j%>,再能过duoxuan<%=j%>写到数据库