Get id of a control inside a datalist inside another datalist

Question

I have a datalist named dlcompCategory and inside it another datalist named dlComp and inside it another datalist named dlitem and inside it I have a radio button named rbOption:

<asp:DataList ID="dlcompCategory" runat="server">
<ItemTemplate>
<asp:DataList ID="dlComp" runat="server">
<ItemTemplate>
<asp:DataList ID="dlitem" runat="server">
<ItemTemplate>
<asp:RadioButton ID="rbOption" runat="server"></asp:RadioButton>
</ItemTemplate>
</asp:DataList>
</ItemTemplate>
</asp:DataList>
</ItemTemplate>
</asp:DataList>

and in code bind a list in the radiobutton. How can I get whether the radiobutton is checked or not in radiobutton onclick event in JavaScript?