Question

Which of these is required to balance the budget for the year?

Revenue equal to spending
Revenue greater than spending
Revenue less than spending
No national debt

Answer 1

Revenue equal to spending.
National debt is practically irrelevant to a balanced budget, given that payments on loans and interest would be factored in to the spending. So basically you can still have a balanced budget with national debt, just as your own personal budget can be balanced as long as you factor in the payments on your debt (credit card payments, mortgage, etc).
In order for the budget to be balanced, you cannot spend more money than what you make, so revenue less than spending won't work.
What makes this question a bit tricky is the option for revenue to be greater than spending. This would be a positive scenario, since it would ultimately lead to a surplus, but on the fundamental level, it is not necessary for a balanced budget.