Command of Evidence SAT question

Choice C is the best answer because it presents the quotation that best illustrates the claim that the speaker is determined to experience the countryside around her. In the quotation, the speaker makes it clear that she plans to walk somewhere based on her own wishes (“where my own nature would be leading”) rather than follow anything else (“another guide”), and that she’ll walk “in ferny glens” alongside the mountain. 

Choice A is incorrect because this quotation suggests that the speaker wants to avoid pursuing money and education (“busy chase of wealth and learning”) and instead return to some earlier interests (her “first feelings”); the quotation doesn’t address her determination to experience the countryside. Choice B is incorrect because the speaker is describing the circumstances under which she won’t walk, which doesn’t address her determination to experience the countryside. Choice D is incorrect because rather than conveying her determination to experience the countryside, the speaker is explaining a particular thing she won’t do (“seek not the shadowy region”).