Anyone proficient with Adobe Acrobat?

I scan LOTS of documents. Recently, all of my letter-sized papers have been scanning to legal-sized Adobe pages. The layout looks weird and awkward, and I need to zoom-in just to read the pages. Does anyone know what I need to do—which option to select and change—to fix this problem?

I’ve tried searching for “help” in Adobe, but I can’t find my answer.