Question

what is a major benefit of schooling? reproduction hydrodynamic efficiency division of labor aerodynamic efficiency

Explanation:

Schooling refers to fish swimming in coordinated groups. A key evolutionary benefit is reduced water resistance, which lowers energy expenditure for movement. Reproduction is not a direct benefit of schooling itself, division of labor is not a primary trait of fish schooling, and aerodynamic efficiency applies to air-breathing organisms, not aquatic fish.

Answer:

hydrodynamic efficiency