What does an upper gi series allow us to see?

Is an x-ray examination of the esophagus, stomach and first part of the small intestine (also known as the duodenum). Images are produced using a special form of x-ray called fluoroscopy and an orally ingested contrast material such as barium.
may be used to help accurately diagnose pain, acid reflux, blood in the stool and other symptoms.

It would be answer choice b (1975)