Please help The caged bird sings with a fearful trill

Of things unknown but longed for still

And his tune is heard on the distant hill for

The caged bird sings of freedom.

Why does the author repeat the stanza shown, what does this represent?

A) It represents that not all people are upset that they don't have freedom

B) To show that people need to fight so that everyone has freedom

C) To show that the caged bird sings because he is unhappy to be trapped in a cage and doesn't know freedom.

D) It captures the feeling that the suffering continues to repeat, rather than end

This is on the Caged Bird by Maya Angelou. Please give and explanation behind your selection if possible.