PHP Regular Expressions
What will be the output of the following PHP code?
$author = "nachiketh@example.com";
$author = str_replace("a","@",$author);
echo "Contact the author of this article at $author.";

Cont@ct the @uthor of this @rticle @t n@chiketh@ex@mple.com
Contact the author of this article at nachiketh@ex@mple.com
Contact the author of this article at n@chiketh@ex@mple.com
Error

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