She replied, "I think the largest contributor to the debt ceiling, or to our deficit, has been the Trump tax cuts."
The Trump tax cuts, officially known as the Tax Cuts and Jobs Act, has been a major factor in ballooning the federal debt, because the reduction in revenues has made it harder for the nation to cover its spending commitments. However, contrary to what Ocasio-Cortez said, the bill that Trump signed has not been the largest factor in increasing the debt, whether you use the debt or annual deficits as the measure.
Politifact ruled the claim FALSE.