21. Which opposition is NOT developed in the essay? (A)nature vs. civilisation (B)freedom vs. authority (C)desire vs. duty (D)emotion vs. reason

17. The belief ______ learners develop grammatical competence primarily through exposure has been challenged by researchers ______ conclusions, which several critics contend ______ insufficiently grounded, have influenced current pedagogical practices. (A)that / whose / are (B)which / that / are (C)which / whose / is (D)that / which / is