Which of the following best describes the position of the U.S. budget, as of fiscal year 2010, when all current spending and future entitlement obligations are taken into account?

A. The deficit is clearly sustainable

B. The deficit is not at all close to sustainability and will require large adjustment to avoid a budget crisis in the future

C. The deficit is so far from sustainability that no possible adjustment of spending or taxes can avoid a crisis

D. The deficit is very close to sustainable, and can be made sustainable with only small adjustments