Correct Answer: C

Rationale: Multiple exposures of small quantities are considered most cariogenic. The total amount of dietary fermentable carbohydrate seems to matter less than the form and frequency in which it is consumed. Having multiple exposures of even small quantities of fermentable carbohydrate throughout the day promotes a highly cariogenic environment in the mouth. Choices A and B, involving single exposures, are less cariogenic as they do not sustain the fermentation process over time. Choice D suggests a beneficial practice by chewing sugarless gum after exposures, which can reduce the risk, making it less cariogenic compared to multiple exposures of small quantities.

Correct Answer: D

Rationale: The correct answer is D. Water regulates body temperature by evaporating as perspiration from the skin, not by pooling. When sweat evaporates from the skin, it takes away heat, which helps cool the body. Choices A, B, and C are correct because water acts as a solvent for chemical reactions, maintains the stability of body fluids, and enables the transport of nutrients and excretion of waste, respectively.

Correct Answer: A

Rationale: Both statements are true. Approximately 75% of reputable producers of bottled water use groundwater as their water source, which is the same source as the public water supply. Plain tap water, coming from underground sources or reservoirs, is indeed a natural source of fluids. The first statement is supported by the fact that groundwater is a common source for bottled water due to its purity and taste. The second statement is true as tap water is sourced from natural reservoirs or underground aquifers in most cases, making it a natural fluid source for consumption. Other choices are incorrect because both statements are factually accurate based on common practices in the production and sourcing of bottled water and tap water.

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: C

Rationale: Vitamin A can be stored in the liver to meet basic needs for at least 1 year. This storage capacity allows the body to have a reserve of Vitamin A to sustain its needs over an extended period. Choices A, B, and D are incorrect because they underestimate the storage capacity of Vitamin A in the liver, which can last longer than these durations.