A dependent clause is a group of words with a subject and a verb, but doesn't make much sense on its own. A lot of times, especially in a sentence with a comma, you can split the sentence and see if it makes any sense.
6. "Before we hiked"
7. "When we go on nature field trips."
8. "Since John was an expert of volcanoes"
9. "If you want to see something closer."
10. "After a volcano erupts"
None of those answers make sense as independent sentences, which is how you can tell they're dependent clauses; they depend on the other part of the sentence.
The final stanza of "A Poem for Mrs. Long, My Librarian" indicates that books gave the speaker comfort and hope during her childhood. Just before this stanza, the reader states that her everyday life is fine, but in this stanza, she informs the reader that books still provided an escape to somewhere more magical than her own world. In the final line, the speaker discusses how her librarian, and the books she shared, were a source of "Spring"(hope) for her.
C) inclusiveness is the answer