It is an example of a idiom.
hope it helps!
The noun in this sentence which is uncountable, meaning that it names something that cannot be counted is the noun water.
You cannot count how many waters there are - it is uncountable. The other nouns, students and pitcher are countable, so they cannot be the correct answers, but rather water is.
I do eat organic food. I eat it because to me it is way better than eating pesticides and gross chemicals. When we eat McDonalds and stuff that stuff is packed with gross stuff. As us humans it is important to eat right no matter the circumstance. when we eat non organic we have side effects like cancer and sorts but with organic we cut those chances in half.
