The correct answer is option D, Giardiasis
Giardiasis is a communicable disease that is spread by the parasite Giardia. Giradiasis is a form of diarrhea and the causative parasite spread through water, soil and food which is contaminated with feces of infected humans and animals. This parasite is resistant to even chlorine disinfection as the outer shell protect it for a longer period of time.