A tax is regressive if it takes a:

a) Larger number of dollars as income falls.
b) Smaller fraction of dollars as income falls.
c) Larger number of dollars as income rises.
d) Smaller fraction of dollars as income rises

A tax is regressive if it takes a  Smaller fraction of dollars as income rises.

A regressive tax takes a greater proportion of the income of lower-income groups than of higher-income groups.

Explanation:

A regressive tax takes a greater proportion of the income of lower-income groups than of higher-income groups.

Some common terminologies with reference to tax

Regressive Tax :A  tax for which the percentage of income paid in taxes decreases as income increases.

Progressive Tax: A tax for which the percentage of income paid in taxes increases as income increases

Proportional tax:A  tax for which the percentage of income paid in taxes remains the same for all incomes

Tax Base:income, property, good, or service that is subject to a tax

Tax Incentive :the use of taxation to encourage or discourage certain behavior

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