What does this /oo/ dash on top mean

Will mark ! : "we have appealed to their native justice and magnanimity, and we have conjured them by the ties of our common kindred to disavow these usurpations, which, would inevitably interrupt our connections and correspondence." these lines from the declaration of independence are an example of the use of (5 points) select one: a. logos b. pathos c. theme d. purpose