Which population would be good to survey to determine a seventh graders favorite books

10 students in one seventh grade class
Five students from each of the 6 seventh grade classes
All 400 7th grade students
15 7th graders who sit together at lunch

All 400 7th grade students would be the best population to survey in order to determine seventh graders' favorite books. This larger sample size would provide a more comprehensive and representative understanding of the general preferences among seventh graders.