The correct option is D A-3, B-4, C-1, D-2
Mucosal epithelium form invaginations in between the bases of villi in the intestine called Crypts of Lieberkuhn.
Each lobule of the liver is covered by a thin connective tissue sheath called the Glisson’s capsule.
The pancreatic islets or islets of Langerhans are the regions of the pancreas that contain hormone-producing cells. They are responsible for producing the insulin hormone along with other hormones.
Sub-mucosal glands called Brunner’s glands present in the duodenum protects the intestinal mucosa from acid as well as provide an alkaline medium (pH 7.8) for enzymatic activities.