The answer is true, you can get healthier off drinking water
The Grapefruit Diet is a common fad diet that promises dramatic results and is only popular for a short period of time.
The correct answer is this one: "human industrialization." Air pollution comes from human industrialization. Because of too much industrialization, there are a lot of excess and wastes in any form: air or even liquid and solid wastes.
A or B are both the best options in this case, but B is the best option overall because if he is interested in an activity, then he will have more motivation.