The correct answer is "The poem has a strict structure, including repetition".The poem "I Hear America Singing" by Walt Whitman has a strict structure particularly the structure of stanza which is a unit of lines grouped together. This poem also includes a lot of repetition of the word "singing" making reference that each people sing their own song.
Everyone likes food, yet not everyone enjoys the same particular food. It has the word yet in the sentence. If you remove yet, then there is two complete sentences present.