Answer:
The answer is: serving size distortion
Step-by-step explanation:
Obesity is one of the common medical conditions that is increasing worldwide. It is the condition of having too much (excess amount) fat in the body. Its common contributing factors are: genetics, metabolic rate, food frequency, diet composition, etc.
In the case of Clarissa and her family, they are living in a poor area of town. This doesn't necessarily mean that they're poor. So, demographics doesn't play as an obesity factor. The situation also didn't mention anything about her family's genes on obesity. Portion control refers to how a person pays attention to the portions of the food he/she eats. Thus, this is not an obesity factor.
Serving size distortion refers to large serving sizes that are considered normal for people. In the case of Clarissa and her family, eating eat-all-you-can restaurants and fast food places with large servings is very normal for them. If they keep on consuming large amounts of food over time, then they'd surely become obese, provided that calorie-in is greater than calorie-out.
Thus, this makes "serving size distortion" as the answer.