it's D but I might be wrong
Amphibians have three heart chamber and they lay eggs so
AMPHIBIAN
The answer is: an "instinct" .
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A bacterium called Vibrio cholerae causes cholera infection. The deadly effects of the disease are the result of a toxin the bacteria produces in the small intestine. The toxin causes the body to secrete enormous amounts of water, leading to diarrhea and a rapid loss of fluids and salts (electrolytes).
