Because it can cause serious infections in the lungs, blood and our brains...It may also cause urinary tract and infections in wounds.
There is an electrical gradient and there is a concentration gradient.
1.) Chemical gradient better known as concentration gradient is much more powerful and compelling than the electrical gradient.
2.) Water is a polar molecule, meaning one side it positively charged while the other is negatively charged. This polar charged molecule causes water to have a weaker electrical gradient, thus the water has to move on its concentration gradient.
It is D because you are inferring the rest are statements the dog barking you can obviously hear it vinegar has a pungent aroma you can smell it. the flower is pink you can see it. but a cup with steam coming from it will be hot to the touch. it says "Will be" which implies that you haven't actually touched it yet. I know which question your talking about.