Jack is a college athlete who requires 2,800 kilocalories a day to support his total energy needs. Even though Jack likes many different foods and makes it a point to try new things, he consumes only approximately 1,600 kilocalories a day. Which one of these characteristics of a healthful diet is Jack missing?

A. adequacy
B. balance
C. moderation
D. variety

Option A; ADEQUACY.

Explanation:

A healthy diet consists of five characteristics: adequacy, balance, calorie control, moderation, and variety.

Nutritional adequacy is the comparison between the nutrient requirement and the intake of a certain individual or population.

Nutritional adequacy is defined as the sufficient intake of essential nutrients, needed to fulfill nutritional requirements for optimal health. The requirement for a given nutrient may be at a lower or higher intake amount.

Since jack requires 2,800 kilocalories a day to support his total energy needs and he consumes only approximately 1,600 kilocalories a day. Then the characteristics of a healthy diet jack is missing is ADEQUACY.

obviously, the latter.