Escape apostrophe in aspx file

How do I escape apostrophes / single quotes in ASP.net XML?

<asp:Button ID="myButton" runat="server"
    OnClientClick='confirm("How do you escape this 开发者_运维问答apos'trophe?")' />

<asp:Button ID="btnClone" runat="server" OnClick="btnClone_Click"
    OnClientClick="confirm('How do you escape this apos\'trophe?')" />

<asp:Button ID="myButton" runat="server"
    OnClientClick='confirm("How do you escape this apos&#39;trophe?")' />