The correct answer is B. Shortened title of work
Step-by-step explanation:
According to style manuals such as the MLA Style Manual in a parenthetical citation which occurs as you quote, paraphrase or summarize an external source and need to acknowledge the authorship you should include both the author and the page in parentheses. However, in the case the author is unknown is recommended to replace the section fo the author for the title of the work of the shortened version of it, this applies to almost any source including articles, web pages, books, etc. Thus, if the author of a source is unknown the information you should include is the shortened title of the work.