Horomones im not sure what are the options of answers
4= very brisk, hyper active w/ clonus, indicative of disease
3= brisker than average, may indicate disease
2= average, normal
1= diminished, low normal
The answer is B. chemicals.
the reason its b is because A= bacteria but u have to clean the bacteria in the water so its not A and its not c. becouse that will be just turning the ice into water .so the answer is b. becouse we use chemicals everyday to get rid of bacteria and waste