45. Which of the following statements about testing is correct? (A) Test reliability can be established when there are many items tested on a big group of students. (B) When a test of oral proficiency is conducted through multiple-choice written test, it has achieved content validity. (C) A norm-referenced test is designed to measure test takers’ abilities based on a specific set of objectives. (D) In order to ensure washback effect of a test, teachers should give feedback to test-takers on their performances.