Answer: suffering
Step-by-step explanation:
Here's the complete question:
I sit and look out upon all the sorrows of the world, and upon all oppression and shame; I hear the secret convulsive sobs . . .
Clara chose this excerpt to help support her interpretation of "The Caged Bird" because it has an extended metaphor that examines
An extended metaphor refers to the version of metaphor which extends over several stanzas, lines, or paragraphs.
With regards to the question, the extended metaphor examines suffering. This can be deduced from the poem where it was written that "I sit and look out upon all the sorrows of the world... "