Read the following lines from Whitman's "Song of Myself" and answer the question.
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The wild gander leads his flock through the cool night, Ya-honk! he says, and sounds it down to me like an invitation; The pert may suppose it meaningless, but I listen close, I find Its purpose and place up there toward the wintry sky.
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When Whitman compares the sound made by a goose to an invitation, he creates an image that stresses_____.
the interpretive powers of humans
a distrust of individualism
the failure of people to connect with each other
the poet's unity with the natural world