<?php $a= “hello”; $b= &$a; unset($b); $b= “world”; echo $a; ?> 下面代码的输出结果是( )。A:hello B:world C:NULL D:unset 答案: hel <?php $a= “hello”; $b= &$a; unset($b); $b= “world”; echo $a; ?> 下面代码的输出结果是( )。A:hello B:world C:NULL D:unset 答案: hel 2021-12-26 8