The sentence that uses quotation marks correctly is One famous song from the movie is "Tonight," a duet sung by the characters Maria and Tony.
Quotation marks are used differently in different countries. Quotation marks are used with direct quotes. When quoting a complete sentence it is capitalized, but it is not capitilized when quoting a fragment. Titles of bigger bodies of work are usually italicized, and titles of smaller pieces within a bigger work are emphasized by using quotation marks.
