Explanation:

- The revenue budget consists mainly of two components: revenue receipts and revenue expenditure.

- Revenue receipts include all money received by the government through taxes and other non-tax sources.

- Revenue expenditure refers to the expenses that the government incurs in its day-to-day functioning.

- Option 1: Income budget - Not a standard term in government financial planning.

- Option 2: Investment Expenditure - Part of capital budget, not revenue budget.

- Option 3: Revenue expenditure - Main component of the revenue budget.

- Option 4: Budget Expenditure - General term, includes both capital and revenue expenditures.