Explanation:

- The Union Budget for 2021-22 introduced a provision where interest earned on Provident Fund contributions becomes taxable if the contribution exceeds a certain amount.

- Option 1, Rs1.5 lakhs: This is a common threshold for other deductions, but not for Provident Fund interest taxation in the 2021-22 budget.

- Option 2, Rs1 lakh: This is incorrect for the context of Provident Fund contributions.

- Option 3, Rs2 lakhs: This threshold is not related to Provident Fund interest taxability.

- Option 4, Rs2.5 lakhs: Contributions above Rs 2.5 lakhs in a year will make the interest earned taxable.