Which excerpt from "A Poem for My Librarian, Mrs. Long” best supports the conclusion that books gave the poem’s speaker a sense of comfort and hope during her childhood?

What is the meaning of "full tide" as it is used in this sentence? before i could explain to her the differences of language in this world, she was embarked on the full tide of another subject. a long and involved argument an inaccurate representation a detailed and lively discussion an uncontrollable flood