Which one of the following is the most accurate statement regarding giardiasis?

Select an option to attempt

1. A
   The drug of choice for giardiasis is chloroquine.
2. B
   Giardia lamblia produces an enterotoxin that increases cAMP within the enterocyte, resulting in diarrhea.
3. C
   Giardia lamblia infection is acquired by ingestion of food or water contaminated with human feces only (i.e. there is no animal reservoir for this organism).
4. D
   Infection by Giardia lamblia occurs principally in the small intestine frequently resulting in the malabsorption of protein and fat.