Correct Answer: A

Rationale: The correct answer is A: Elderly. The other choices provided, low income, vegans, and chronic disease, alcoholics, are also at risk for nutritional deficiencies but the question specifically asks for 4 groups out of the 12 discussed. The 12 groups at risk for nutritional deficiencies include the elderly, low income individuals, vegans, chronic disease, alcoholics, smokers, periods of growth, individuals with medical conditions, physical stress, physiological stress, those on polypharmacy, and those with inadequate intake. The question focuses on identifying 4 out of these 12 groups, making 'Elderly' the correct choice.

Correct Answer: D

Rationale: The correct answer is D, Perspiration. Water loss can occur through respiration inflammation, strenuous exercise, and diarrhea. Perspiration, also known as sweating, is a mechanism by which the body regulates temperature and eliminates some waste products, but it is not a cause of water loss. The body loses water through sweating, but this loss is mainly for cooling purposes, and it is not a primary mechanism for water loss like respiration, exercise, or diarrhea.

Correct Answer: C

Rationale: The correct answer is Vitamin D. Although vitamin D, also known as calciferol, has been called a vitamin, it is more appropriately classified as a hormone. Like hormones, vitamin D acts to control the function of other cell types. For example, it helps the body absorb and regulate skeletal calcium and phosphorus levels. Choice A (Vitamin A) plays a crucial role in vision and immune function. Choice B (Vitamin B) is a complex of different vitamins that play various roles in the body. Choice D (Vitamin C) is important for collagen production and acts as an antioxidant.

Correct Answer: D

Rationale: The correct answer is D, Osmosis. Osmosis is the process where water moves from an area of low solute concentration to an area of high solute concentration. This movement equalizes the solute concentration in intracellular and extracellular fluids. Choices A, B, and C are incorrect because they do not describe the movement of water based on solute concentration levels.

Correct Answer: C

Rationale: The first statement is true; the second is false. If a deficiency of one vitamin is suspected, symptoms of other vitamin B deficiencies also may be present. Folate deficiencies usually occur with other nutrient deficiencies. Specifically, folate functions in conjunction with vitamins B12 and C in maintaining normal levels of mature red blood cells.