The excerpt contains the theme of Great Britain opposing other nations. Great Britain supporting other nations. Great Britain opposing slavery. Great Britain supporting slavery.

This question is missing the excerpt. I've found the complete question online. It is the following:

Read the excerpt from “The Morning Dream.”

Awaking, how could I but muse

At what such a dream should betide?

But soon my ear caught the glad news

Which serv'd my weak thought for a guide—

That Britannia, renown'd o'er the waves

For the hatred she ever has shown

To the black-sceptred rulers of slaves,

Resolves to have none of her own.

The excerpt contains the theme of

Great Britain opposing other nations.

Great Britain supporting other nations.

Great Britain opposing slavery.

Great Britain supporting slavery.

The excerpt contains the theme of:

C. Great Britain opposing slavery.

Explanation:

That Britannia, renown'd o'er the waves

For the hatred she ever has shown

To the black-sceptred rulers of slaves,

Resolves to have none of her own.

The lines above are the last ones in the poem "The Morning Dream", by William Cowper. And they contain the answer we need. According to the them, Britannia, or Britain, "resolves to have none of her own". "None" refers to the "slaves" mentioned in the previous line. This means Britain opposes slavery, that the country will not allow slavery in its own territory. For that reason, the best option is letter C.

did you ever get an answer? i'm on the same question : (