Water based disease is
**Core Concept**
Water-based diseases, also known as waterborne diseases, are illnesses caused by pathogens that are transmitted through contaminated water. These diseases can be caused by bacteria, viruses, or parasites that are present in the water supply.
**Why the Correct Answer is Right**
The correct answer is a disease caused by a parasite that is commonly associated with contaminated water. Giardiasis, caused by the protozoan parasite Giardia lamblia, is a waterborne disease that affects the small intestine, leading to diarrhea, abdominal cramps, and weight loss. Giardia is typically ingested through contaminated water, food, or contact with an infected person.
**Why Each Wrong Option is Incorrect**
**Option A:** Cholera is a waterborne disease caused by the bacterium Vibrio cholerae, but it is not the correct answer because the question asks for a disease that is caused by a parasite, not a bacterium.
**Option B:** Amoebiasis is a waterborne disease caused by the protozoan parasite Entamoeba histolytica, but it is not the correct answer because the question asks for a disease that is specifically caused by Giardia lamblia.
**Option C:** Dysentery is a waterborne disease caused by the bacterium Shigella, but it is not the correct answer because the question asks for a disease that is caused by a parasite, not a bacterium.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that waterborne diseases can be prevented through proper water treatment, safe storage, and handling. Giardiasis can be treated with antiparasitic medications, but prevention is key to avoiding this disease.
**Correct Answer: C. Giardiasis**