Why is the careful observation of the key sentence important in identifying the main idea of a paragraph?

Javier is writing a literary analysis of the secret garden. read this introduction to his essay. frances burnett’s “the secret garden” explores the challenges of a sickly, self-centered little girl named mary lennox. after mary’s parents die of cholera, she moves from india to england to live at her uncle’s estate in yorkshire. while living at the old estate, mary discovers an abandoned garden that belonged to her deceased aunt. tending to the neglected garden brings mary joy, and her health improves. through mary’s transformation, burnett presents nature as a symbol of rebirth and healing. which piece of textual evidence should javier use to support the claim made in the introduction? a. “‘it’s in the garden no one can go into,’ she said to herself. ‘it’s the garden without a door. he lives in there. how i wish i could see what it is like! ’” b. “in india she had always felt hot and too languid to care much about anything. the fact was that the fresh wind from the moor had begun to blow the cobwebs out of her young brain and to waken her up a little.” c. “mary felt lonelier than ever when she knew she was no longer in the house. she went out into the garden as quickly as possible, and the first thing she did was to run round and round the fountain flower garden ten times.” d. “‘it isn’t a quite dead garden,’ she cried out softly to herself. ‘even if the roses are dead, there are other things alive.’”