Where is the XML exception?

Where is the XML error? & Lt ;? Phpheader ('content-Type: text/XML'); echo '& lt ;? Xmlversion = & quot; 1.0 & quot; encoding = & quot; UTF-8 & quot ;? & Gt; where are XML errors?
Header ('content-Type: text/XML ');
Echo' ';
Echo' ';
$ Link = mysqli_connect ('localhost', 'root', 'root', 'tbr _ 121d ')
Or die ('fail to connect to the database ');
$ Query = "SELECT * FROM drill ";
$ Result = mysqli_query ($ link, $ query );
While ($ row = mysqli_fetch_object ($ result )){
Echo' '. $ Row-> question .' ';
Echo' '. $ Row-> option_a .'';
Echo' '. $ Row-> option_ B .'';
Echo' '. $ Row-> option_c .'';
Echo' '. $ Row-> option_d .'';
}
Echo' ';
Mysqli_close ($ link );
?>

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The XML page cannot be displayed.
XML input cannot be viewed using the XSL style sheet. Correct the error and click refresh or try again later.


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An XML document can have only one top-level element. An error occurred while processing the resource 'http: // localhost/loading_drill. Row 2nd, Location: 2

Warning: Cannot modify header information-headers already sent by (output started at C: \ AppServ \ www \ lo...
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