Proportional tax requires constant rate across incomes Steps:

• Recall proportional tax definition: same percentage rate applied to every income level.
• Note income levels from table are needed to compute rates (tax divided by income).
• Without specific income values provided, cannot verify rates for any option.
• Table omission makes determination impossible.

Why C is correct:

• Cannot confirm; lacks income data to show constant rate per tax theory.

Why the others are wrong:

• A: Insufficient data to assess rates.
• B: Insufficient data to assess rates.
• D: Insufficient data to assess rates.

Final answer: Not enough information.