The correct answer is C. Do foreign language classes help students improve in other subjects?
Explanation
Secondary questions are questions that serve as specific objectives in an investigation, their function is to contribute to the investigation of a topic from a specific subject. For example, Kayla is working on a research project asking if foreign language classes should be required for high school students; an adequate secondary question for this topic would have to inquire about the relationship between foreign languages in high school students and why this should be required. So, the correct answer is C. "Do foreign language classes help students improve in other subjects?" because this option relates the academic performance of the students in other areas with the learning of foreign languages; that in the case of Kayla's research, if it were shown with this secondary question that effectively learning foreign languages contributes to the improvement of students in other areas, it would help to support her main question of whether these languages should be required in high school.