Answer:
Letter C is the correct answer.
Step-by-step explanation:
No Child Left Behind (or NCLB) was a law for K-12 Education in the U.S. between 2002 and 2015 (it was replaced by Every Student Succeeds Act that year) and the main issue was how children were learning at school.
Options A, B, and D are related to the academic status of the professor, since A talks about tests taken by teachers; letter B refers to state qualifications in the area teachers have in charge; letter D also talks about how professors can prove they are able to teach their subjects: all these options are strictly related to how children can learn and how exams and certifications can help teachers in this task. On the other hand, Letter C does not relate directly to students' performance in the classroom, and that is why this is the correct answer.