This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: NEET 2019, Subject name: Pathology
Flask shaped ulcers intestine caused by which of the following? 
Select and explain. 
A. Typhoid, B. TB, C. Entamoeba histolytica, D. Giardia
C: Entamoeba histolytica
Answer: C: Entamoeba histolytica 
Explanation: Infection Ulcer Typhoid Longitudinal ulcer TB Transverse ulcer Entamoeba Histolytica Flask shape ulcer Broad base ulcer(flask shape ulcer) is seen in entamoeba histolytica. Giardia is a noninvasive cause of malabsorption.