Final answer:
The correct punctuation to use when quoting separate lines of a poem is a forward slash (c). This style is applied when quoting up to three lines of poetry, and no quotation marks are used for longer quotations which are indented instead.
Step-by-step explanation:
When quoting poetry, to designate separate lines you place a forward slash between the lines in the quotation. Therefore, the correct answer is c) Forward slash. When quoting one to three lines of poetry, you should use quotation marks around the poem's excerpt and separate each line with a forward slash.
Remember that when quoting more than three lines, you should format them differently by indenting the quotation one-half inch from the rest of your text, in which case, quotation marks are not required. It's also essential to note that punctuation such as colons and semicolons should go outside the quotation marks unless they are part of the quoted material.