In a progressive tax system, O A. the marginal tax rate increase as income increases but the average tax rate does not change as income increases. O B. the marginal tax rate and the average tax rate increase as income levels increase and the marginal tax rate exceeds the average tax rate. O C. the marginal tax rate and the average tax rate are the same for every income level and the same as income increases O D. the marginal tax rate and the average tax rate decrease as income levels increase and the marginal tax rate is less than the average tax rate