When writing out the names of his sources by hand, Carlos should underline the titles of longer works, such as books, while using quotation marks for shorter works like songs, poems, and essays. According to this guideline:
- He should underline Justice and her brothers, a book by Virginia Hamilton.
- He should use quotation marks for the other titles: “You showed me the way,” “Let America be America again,” and “Of the meaning of progress.”
Therefore, the title he should underline is Justice and her brothers.