Most, not all

Althouse notes the unsure answer by Rep. Elijah Cummings on Benghazi.
He could have said — like many Democratic Party partisans — that the matter has been thoroughly investigated and it's nothing more than partisan politics now. But he said "I don't know." Twice. And then he said "they have resolved most of the questions." Most. Most means not all. So clearly there are questions left.