Answer:
The sound device that is emphasized in both of the passages is C. repetition.
Explanation:
In poetry, repetition helps create a rhythmic pattern as well as emphasize an idea. It can consist of repeating the same word or phrase, sometimes even whole lines. In the passages we are studying here, we can notice the repetition of a several words and phrases:
By the shores of Gitche Gumee,
By the shining Big-Sea-Water,
Stood the wigwam of Nokomis,
Daughter of the Moon, Nokomis.
Dark behind it rose the forest,
Rose the black and gloomy pine-trees,
Rose the firs with cones upon them;
Bright before it beat the water,
Beat the clear and sunny water,
Beat the shining Big-Sea-Water.
(Henry Wadsworth Longfellow, "The Song of Hiawatha")
We rest.—A dream has power to poison sleep;
We rise.—One wandering thought pollutes the day;
We feel, conceive or reason, laugh or weep;
Embrace fond woe, or cast our cares away:
(Percy Shelley, "Mutability")
Note that there are other sound devices being used, but the most evident one is repetition, especially in Longfellow's poem. In Shelley's poem, the plural subject is being emphasized. The repetition of "we" aims to show readers how life and death are the same for all of us.