The parents may feel that slavery is okay to a certain extent because there parents raised them that way and they May have grandparents that owned some "slaves." Now children's attitudes might be different because nowadays you encounter lots of nationalities and races in the USA and were starting to adapt and open up to them wanting to know more about what they do or why they do something different than you might do.
To tell readers what they are looking at and why is the image is relevant
The answer is D. All of the other claims focus on giving the students an easier time at the expense of the school, while answer D makes the argument that it would benefit the school.
