In the given passage, (S1) the introduction, discusses the life of ‘sustainability’. (S1) is followed by (Q), which contradicts a little what is said in (S1). (Q) is followed by (P) as it reaffirms what is mentioned in (S1). (P) is followed and expanded by (S). (S) is followed by (R), which discusses about the result of what is discussed in (S1), (Q), (P), and (S). (S6) is the final conclusion, as per question, of the passage.