Answer:
The water is hypotonic to the body of the patients
Explanation:
<em>Pure water is generally hypotonic to the red blood cells in the body of humans. Hence, if a person is hooked up to an IV line that included pure water, the red blood cells in the person's body will take-in water, become turgid, and then start lysing. This will make the person become sick or even cause death in severe cases.</em>
One problem with this hypothesis is that the student didn't write about why this hypothesis might work - what is the underlying mechanism. The thing is that one might want to write the underlying mechanism or explanation in his hypothesis. Another problem with this hypothesis is that it's very hard to measure and be sure that following exposure to white chocolate, people are happier and that it's not a consequence of something else.
4 is true I learned that the hard way