<?php
$data = htmlspecialchars($data);
echo $data;
When you use a blade echo {{ $data }} it will automatically escape the output. It can only escape strings. In your data $data->ac is an array and $data is an object, neither of which can be echoed as is. You need to be more specific of how the data should be outputted. What exactly that looks like entirely depends on what you're trying to accomplish. For example to display the link you would need to do {{ $data->ac[0][0]['url'] }} (not sure why you have two nested arrays but I'm just following your data structure).
@foreach($data->ac['0'] as $link)
<a href="{{ $link['url'] }}">This is a link</a>
@endforeach