Which of the underlined titles in the following sentence should be enclosed in quotation marks? our textbook, _english_literature_, includes shakespeare's play _romeo_and_juliet_ and edgar allen poe's poem _the_raven_. (the _ are for which titles were underlined! plzzz )

The Raven. 

Quotation marks go around anything that is part of a whole collection, or something that is short in nature.

A textbook would be a long work that is self-standing (meaning that it is not part of a whole), therefore it would need to be underlined or italicized; note, a chapter of a textbook, for instance, would be italicized because it is part of a whole work. 

Romeo and Juliet would be underlined as well because it is a play that is self-standing and it is not a short work.