Explanation should include

United States Department of Agriculture (USDA) dietary guidelines
macronutrients and micronutrients (e.g., protein, carbohydrate, fat, vitamin, mineral)
product labeling
diet (the food one eats) vs. diet (the process of maintaining a healthy weight)
weight management
hydration.

Process/Skill Questions:

How do the different components of My Plate relate to diet?
What are the caloric values of protein, carbohydrate, and fat?
How do nutrients affect diet? What percentage of the diet should be made up of each nutrient? How may this vary based on activity level?
What are typical weight management goals? How can they be achieved?
What roles do specialized diets play in weight management? What are the pros and cons of fad diets?