There are different foods that you can eat without getting weight. Basically, people eat until they feel full, this satiety is achieved better eating rich protein food. The strategy is to feel satiated eating the less calories possible, like cakes for example.
So, basically eating only protein, you won't get weight, because you are getting satiated with no calories.
The correct answer is D. a substantial lunch. A. is unhealthy and carbs turn to sugar which will overload your system. B. is too late in the day and your body can't process it. C. is not only unhealthy, but your body will break down.
The technique that the advertising company used to persuade the viewer to use the diet pill was that they are using 'plain folks' to have the viewer relate.
