Which one of the following items comprises the major portion of Revenue Expenditure in Budget 2025-26 of the Union Government of India?

Interest payments on the public debt consistently constitute the LARGEST single component of the Union Government's revenue expenditure. In the Union Budget 2025-26, interest payments account for the major portion of revenue expenditure (around a quarter of the total expenditure), reflecting the cumulative debt burden of the government. Pension, defence services and road transport are significant but smaller categories. Hence option (b) is correct.