This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Abdomen and pelvis, Subject name: Anatomy
Lining of gallbladder mucosa is 
Select and explain. 
A. Cuboidal, B. Transitional, C. Columnar, D. Squamous
C: Columnar
Answer: C: Columnar 
Explanation: The gallbladder wall's innermost surface is lined by a single layer of columnar cells with an apical brush border of microvilli, very similar to intestinal absorptive cells. Underneath the epithelia is an underlying lamina propria, a muscular layer, an outer perimuscular layer, and serosa. Unlike elsewhere in the intestinal tract, the gallbladder does not have a muscularis mucosa, and the muscular fibres are not arranged in distinct layers. ref - BDC 6e vol2 pg292