47. Which of the following statements can be inferred from the passage? (A) All the views in this passage are strictly based on theoretical deduction without any empirical evidence. (B) Before the methodological issue can be resolved, a clearer picture regarding the best attainable state in the L2 cannot be obtained. (C) Whether future research can produce fruitful insights depends crucially on analytical innovation. (D) Results from achievement tests provide a valid and complete picture of L2 learners’ overall proficiency profile. (E) All existing studies have seriously considered Birdsong’s suggestion.