To strengthen the argument that a school should adopt longer lunch breaks to improve student focus, which option provides the strongest support?

• A. Evidence that longer breaks correlate with improved attention in students.
• B. Anecdotes from teachers about fatigue.
• C. Data showing lunch costs have risen.
• D. A controlled trial showing longer breaks improved sustained attention in students across multiple schools.

Answer: (D)

The strongest support comes from evidence that can show cause and effect across different settings. A controlled trial that demonstrates longer lunch breaks lead to improved sustained attention in students across multiple schools directly tests the policy change, controls for other influencing factors, and shows the effect persists in various environments. This combination—experimental design plus generalizability—gives a strong basis for arguing that longer breaks actually improve focus.

By contrast, evidence that merely shows a correlation between longer breaks and better attention cannot establish causation; other variables could be driving the relationship. Anecdotal teacher reports are helpful for context but are subjective and not systematically reliable. Data about rising lunch costs is not connected to student focus and thus doesn’t bolster the argument about effectiveness.