Specific disease processes and ingestion of certain foods and medications may change the appearance of the stool. If blood is shed in sufficient quantities into the upper gastrointestinal (GI) tract, it produces which change in the stool appearance?

The correct answer is - tarry black.

Explanation:

Black stools is a serious symptom that suggests that it is because of huge amount of the bleeding into the GI or gastrointestinal tract and especialy upper portion of it that include stomach, esophagus, and duodoneum.

As the RBCs are digested by the digestive enzyme in the intestine which makes the stool color to the tarry black which can be also be occur in the tarry black due to medications.

Thus, the correct answer is - tarry black.