Timur on July 21, 2015
The argument establishes that a diet high in nutrition is the cause for an improvement in behavior, the effect. As a general rule, is it acceptable to strengthen an argument the way (E) does, by demonstrating without the cause (a diet low in nutrients) there is no effect (no improvement in behavior).
If the argument were to establish that sunshine leads to healthy plants, and if it is true that cloudy weather (no sunshine) does not lead to healthy plants, is the argument strengthened?
Melody on July 28, 2015