Correct Answer: A

Rationale: Infants are particularly vulnerable to malnutrition due to their high growth rate and specific nutrient requirements. During the first year of life, infants experience rapid growth and development, requiring essential nutrients for proper physical and cognitive development. Teenagers, young adults, and middle-aged adults have more stable nutritional needs compared to infants, making them less vulnerable to malnutrition. Therefore, infants are the most susceptible age group when it comes to malnutrition.

Correct Answer: C

Rationale: The correct answer is C: 'Appropriate amounts of food from each food group.' MyPlate food guidance focuses on portion sizes from different food groups to promote a balanced diet. Choices A, B, and D are incorrect because MyPlate emphasizes the consumption of a variety of foods from different food groups rather than focusing solely on macronutrient percentages, exchange lists, or specific nutrient amounts.

Correct Answer: D

Rationale: The correct answer is D: carbohydrates, meat and meat substitutes, and fats. The most recent edition of Choose Your Foods: Exchange List for Diabetes categorizes foods into these three groups for easier meal planning. Choice A is incorrect because it does not include carbohydrates and groups bread with fruits and vegetables. Choice B is incorrect because it separates carbohydrates into starches and sugars, which are usually counted together in diabetes meal planning. Choice C is incorrect as it does not specifically categorize foods into carbohydrates, meat, and fats as per the latest edition.

Correct Answer: A

Rationale: Individuals with optimal nutritional status differ from those with marginal nutritional status in their nutrient reserves. Optimal nutritional status implies having adequate nutrient reserves, which is lacking in marginal status. Clinical signs (choice B) may or may not be present in both groups and are not the differentiating factor between optimal and marginal statuses. Body weight (choice C) can vary for reasons other than nutritional status. The risk of mental illness (choice D) is not directly related to the comparison between optimal and marginal nutritional status.

Correct Answer: A

Rationale: The correct answer is A: 'nutrient reserves are depleted.' Signs of malnutrition manifest when the body's reserves of essential nutrients are exhausted and can no longer sustain health. Choice B is incorrect because excessive nutrient intake exceeding daily needs does not lead to malnutrition but may cause other health issues. Choice C is incorrect as restricting energy intake may lead to weight loss but not necessarily malnutrition. Choice D is also incorrect as increasing caloric expenditure does not directly cause malnutrition.