in the webassist/email/templates folder, open the template file for your email.
In code view, near the top will be the following code:
$removeBegins = array();
$removeBegins[] = "Security";
add new items using the name of your submit button and select list. for example, if the select list is name "bcc_select" and the submit button is named "email_submit":
$removeBegins = array();
$removeBegins[] = "Security";
$removeBegins[] = "bcc_select";
$removeBegins[] = "email_submit";
this will ignore those form elements in the email body