11. A so                      B since                             C provided                    D though

12. A serve                 B satisfy                           C upset                          D replace

13. A confirm             B express                         C cultivate                    D offer

14 A guarded              B followed                       C studied                       D tied

15. A concepts            B theories                        C divisions                    D convenience

16. A excludes           B questions                      C shapes                       D controls

17. A dismissed          B released                        C ranked                       D distorted

18. A suppress            B exploit                          C address                       D ignore

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