2021 Part D Quiz Answer questions and submit quiz for results. You can learn more about Medicare Part D tier costs. Which tiers cover generic drugs? Tier 1 Tier 2 Tier 3 Tier 4 Tier 5 Part D deductible applies to which tiers? Tier 1 Tier 2 Tier 3 Tier 4 Tier 5 How much is Part D deductible in 2021?The 2021 Part D deductible is Time is Up!