Answer:
Option D, gastrointestinal
Explanation:
Thought it may seem restrictive to only two regions of the digestive tract, the term gastrointestinal, option C, spans the entirety of the extensive tubing system responsible for the ingestion of food, breaking down and metabolism of content into nutritional products, and the elimination of waste.
The gastrointestinal (GI) tract starts with the mouth, also called the oral cavity. It then descends into the pharynx which then becomes the esophagus. The esophagus continues into the stomach. The stomach opens up to the small intestine, broken into three components: the duodenum, the jejunum, and the ileum. The long and winding small intestine gives way to the large intestine, name such because of its wider diameter than the small intestine. The large intestine consists of the cecum (off which the appendix resides), ascending colon, transverse colon, descending colon, and sigmoid colon. Waste is finally expelled via the rectum and anus.
Why Not Other Choices:
Enteric and gastric are both terms attributed to solely the stomach within the GI tract. As the name may suggest, intestinal only refers to its two namesakes: the small and large intestines.
