Explanation:

- In the Union Budget for 2020-21, the income tax rates for individuals were structured based on slabs.

- For annual taxable income above ?15 lakh, the tax rate was set at 30%.

- Option 1, 10% is incorrect, as this rate applies to much lower income brackets.

- Option 2, 20% is incorrect, as it pertains to a different income slab, specifically ?12.5 lakh to ?15 lakh.

- Option 3, 5% is incorrect, as it applies to income between ?2.5 lakh and ?5 lakh.

The correct answer is:

- Option 4: 30%