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Read the following excerpt:
Giardiasis is an intestinal disease caused by Giardia lamblia, a water-borne protozoan. Giardia is carried by humans and some domestic and wild animals. Giardia may contaminate lakes and streams. All water or melted snow must be treated by boiling for at least five minutes, using an iodine-based purifier or using a Giardia-rated water filter. Associated symptoms include chronic diarrhea, abdominal cramps, bloating, fatigue, and loss of weight. Treatment by a physician is necessary to kill the organisms.
Giardiasis is _________
A) is a bacteria found in fruits and vegetables.
B) a mountain in Yosemite
C) a disease that causes stomach problems
D) a sickness that is similar to the common cold.
C) a disease that causes stomach problems