Shortcodes, Protected Content, Levels, No Commenting on Posts

I’m having multiple issues with Membership. This is one of many. I have Stranger and Free as two of my levels. My negative rules are comments, more tag and downloads. What has to be absolutely set for strangers not to be able to comment on posts?

(Never mind. I realized that in Settings > Discussion, the option “Users must be registered and logged in to comment” must be checked)