stripslashes
Inversely escape an escaped string
Remove the backslash:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token keyword">echo</span> <span class="token function">stripslashes</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Who\'s Bill Gates?"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>