In the given passage, (S1) is the introduction, which starts discussion about decentralized planning. (S1) is followed by (S), which discuss about the implementation of decentralized planning. (S) is followed by (R), which discusses about the functions of decentralized planning. (P), which provides the feature of decentralized planning, follows (R). (Q) narrates about the next feature of the planning and follows (P). (S6) is the final conclusion, as per question, of the passage.