The answer is option D "Wordsworth felt lonely until he saw some beautiful daffodils. Now, when he is lonely again, he simply has to think of the daffodils to feel better." In the poem when he seen the daffodils he thought of them as if they are in a long crowd and dancing which makes his heart "feel with pleasure." So in the final stanza he was on his couch and he thought of the flowers again and he was happy again because of his relationship with nature.
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