We're looking for support from the passage for our answer choice for which device Rawls uses to explain his theory.
Answer (A) is correct. Rawls uses a thought experiment to explain his theory. In Lines 36 through 43, Rawls's outline of a thought experiment is explained, and it helps the reader understand his idea of the veil of ignorance more clearly. the words "thought experiment" are explicitly stated in Line 36, so we have clear support for answer (A).
Answer choice (D) is incorrect because Rawls does not use a deduction from a few basic principles to explain his theory. If this were true, he would not have used the thought experiment and would have instead used some type of general principle to explain his theory.
Does this answer your question? If not, let us know, and we'll be happy to provide more clarification.
