Final answer:
The correct answer is option A, validity, because if a test can be done well without having read the book or attended class, it's not measuring what it's supposed to measure.
Step-by-step explanation:
If a student could do well on a test without having read the book or attended class, then the test likely has rather low validity. Validity refers to the extent to which a test measures what it is intended to measure. In this case, if the knowledge and understanding that should have been gained from the book and the class are not required to perform well on the test, the test is not a valid measure of the student's grasp of the subject matter covered in the course work. On the other hand, reliability refers to the consistency of a test's results. Standardization ensures that the test is administered similarly to all test-takers. An operational definition provides a clear, measurable definition of a concept, which helps ensure that a study is replicable and reliable.
Therefore, among the options given (A. validity, B. operational definition, C. reliability, D. standardization), option A, validity, is the correct answer.