PHP output of strange related problems Ah! Ask God to help me look at my little brother. Strange characters that I haven't seen in a day

PHP output strange problem Ah!!! Ask God for help look at the weird characters I've been looking at for a day without knowing where to look.
First I started learning PHP and wrote a process of outputting json after reading from the database.

It looks like the result is right. And then I went to a check site to prompt me　
So I looked for a long reason to find that I do not know where to come in front of the string there are 4 of inexplicable things ...

Excuse me, where is this coming from? = = How do I get rid of it ...
Function index ()
{
$CC =new Demodao ();
$resu = $CC->index ();
$json =json_encode ($resu);
$json =urldecode ($json);
$total = 24;
$json = "{". ' " Total "'.": $total, ". '" Rows "'.": ". $json."} ";
Echo $json;
}
The final output of the JSON

Ask the great God to help me see ~!!!!!!!!!!!! The codes are all utf-8.
------to solve the idea----------------------
is obviously BOM header

