The question says,'if you can log into a website to edit or delete content that has been added by you or another user, you are most likely usingThe correct option is A. Wiki application is a collaborative software runs by wiki which allows users to create and edit enteria through a web browser.
A Wiki application. Wikipedi.a (or any Wiki, for that matter), can be added to, modified or deleted by anyone who visits the site; it is a collaborative contribution.
A Twitter account, blog window, and a Facebook account, all require a secure password that only you would know. So unless you got hacked or something, what you have described would not apply to these three.