Answer:
The independent variable will be the types of food that the participants consume.
The dependent variable would be the amount of nutrients ingested through these foods.
The control variable would be the symptoms related to nutritional deficiencies that the participants felt.
Step-by-step explanation:
An independent variable is one that influences an element within the experiment, while the dependent variable is one that is influenced, by the independent variable, to present an observable result. In the case of the above experiment, as the researcher wishes to assess the influence of vegan and vegetarian food on nutrient intake, we can consider that the independent variable is the types of food eaten, while the dependent variable is the amount of nutrients eaten.
A control variable, on the other hand, is one that is also influenced by the independent variable, but presents a secondary result, in relation to what is being researched. In this case, eating vegan and vegetarian foods can make participants in the experiment feel symptoms related to nutritional deficiencies, such as fatigue, lack of disposition, weakness, among others. As the experiment wishes to assess nutrient intake, symptoms of nutritional deficiency can be considered a control variable.