Correct Answer: C

Rationale: The correct answer is C because MyPlate actually provides more specific guidance compared to MyPyramid. MyPlate was designed to simplify the dietary recommendations for consumers by focusing on a visual representation of a plate divided into food groups, making it easier to understand and apply. Choices A, B, and D accurately describe features of MyPlate: replacing MyPyramid, providing personalized dietary guidance through an interactive website, and grouping foods with similar nutrients while emphasizing proportionality of food selections.

Correct Answer: A

Rationale: The correct answer is A: 'Blood clotting, transmission of nerve impulses, muscle contraction and relaxation.' Calcium plays a crucial role in various physiological functions such as blood clotting, transmission of nerve impulses, muscle contraction and relaxation, membrane permeability, and activation of certain enzymes. Choice B is incorrect because while calcium is involved in calcium homeostasis, it is not the only role it plays in the body. Choice C is incorrect as calcium indeed has several known metabolic functions, and it is not solely for preventing caries. Choice D is also incorrect as the functions mentioned are primarily carried out by other nutrients and not specifically by calcium.

Correct Answer: A

Rationale: Both statements are true. The effect of vitamin A on the growth of soft tissues and bones naturally extends to the teeth and surrounding structures. Enamel hypoplasia, involving defective enamel matrix and incomplete calcification of enamel and dentin, can be due to vitamin A deficiency. The effect of this vitamin upon surrounding bone directly affects spacing patterns of the teeth within the bone and dentition. Choice A is correct because both statements accurately describe the influence of vitamin A on tooth development. Choices B, C, and D are incorrect as they do not reflect the accuracy of the statements provided.

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: A

Rationale: Both statements are true. Systemic diseases can often present with oral manifestations before other systemic signs appear. Additionally, oral diseases can have systemic implications by affecting a person's overall health, such as through inflammation or compromised nutrient intake. Choice B is incorrect because both statements are true, as supported by medical literature. Choice C is incorrect because the second statement is also true. Choice D is incorrect because the first statement is true.