This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: parasitic infection, Subject name: Medicine
Which of the following leads to colonic ulcers? 
Select and explain. 
A. H. Pylori, B. Campylobacter jejuni, C. B. Coli, D. E. Histolytica
D: E. Histolytica
Answer: D: E. Histolytica 
Explanation: E. Histolytica - Acquired faeco-oral route - Exists as trophozoite and cyst forms - Development of Flasked shaped ulcer in the colon - RX :-For Asymptomatic carriers :- Iodoquinol/Paromomycin can be used For Acute colitis:- Metronidazole/Tinidazole can be used