Answer is A. Its been increasing over time.
National Debt is not necessarily a bad thing to have for governments as long as the debt does not accumulate to over 125% of a country's GDP. At that level, national debt is said to be unsustainable. US debt to GDP is around 70% according to the CIA, this is a perfectly acceptable level. Although the debt value itself is actually rising, its percentage value against GDP is what is important about it.
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