This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Microbiology
Which of the following infestations leads to malabsorption? 
Select and explain. 
A. Giardia lamblia, B. Ascaris lumbricoides, C. Necator americana, D. Ancylostoma duodenale
A: Giardia lamblia
Answer: A: Giardia lamblia 
Explanation: Ans. (a) Giardia lamblia Remember: Ascaris lumbricoides in small intestine usually cause no symptoms. In children it may cause pain and intestinal obstruction sometimes complicated by perforation, intussusception or volvulus. Migration to aberrant site can cause biliary colic, cholecystitis, cholangitis, pancreatitis or rarely intrahepatic abscess. Intestinal phase of A.duodenale cause epigastric pain, inflammatory diarrhea and iron deficiency anemia.