How to write by Response.write tag in this place!

Hello everybody, sorry english my bad. :(. I'm write <a> tag by Response.write:
Response.Write("<a rel=" + "lightbox[TeethNo18]" + " runat=" + "'server'" + "href=" + xray[i].ToString() + "></a>");
But not in this place. When i view source code, it's show at top of web. Please help me. Thanks
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