Thanks a lot Bruno Vandekerkhove for make a plugin for solve this problem.
I am not a professional developer but i try to solve the problem another way.
first time i clone and add a page /qa-include/app/q-list.php to /qa-include/app/a-q-list.php
after that i add
if($fields['raw']['categoryid'] != 66)
{
$qa_content['q_list']['qs'][] = $fields;
}
by replace
$qa_content['q_list']['qs'][] = $fields;
on /qa-include/app/a-q-list.php
after that i edit activity page /qa-include/pages/activity.php
require_once QA_INCLUDE_DIR.'app/q-list.php'; to require_once QA_INCLUDE_DIR.'app/a-q-list.php';
Then I able to remove my category question from the activity page. My category id was 66