Correct Answer: C

Rationale: Protein is crucial for tissue repair and recovery after surgery. Proteins provide the building blocks necessary for tissue healing and regeneration. Fats are important for various bodily functions but are not as directly involved in tissue repair as proteins. Carbohydrates provide energy but do not play a primary role in tissue healing. Fiber is essential for digestive health but is not a nutrient that directly promotes tissue repair.

Correct Answer: B

Rationale: A condition that is conducive to the development of dental caries is described as cariogenic. Cariogenic refers to foods or conditions that promote the development of dental caries by providing an environment for bacteria to thrive and produce acids that erode tooth enamel. Choice A, periodontal, is incorrect as it relates to the supporting structures of the teeth rather than the development of dental caries. Choice C, gingival, is also incorrect as it pertains to the gums rather than the causation of dental caries. Choice D, bacteriophilic, is not the term commonly used to describe conditions that lead to dental caries, making it an incorrect choice.

Correct Answer: B

Rationale: The correct answer is B: sulfur. Sulfur-containing amino acids like cysteine and methionine play a crucial role in forming disulfide bonds within proteins. These bonds are essential for the proper folding and structural stability of proteins. Phosphorus (choice A), selenium (choice C), and iron (choice D) do not directly contribute to shaping proteins through bond formation.

Correct Answer: B

Rationale: The correct answer is B, milk. Milk is known for being one of the best dietary sources of calcium, essential for bone health and various bodily functions. Soy products, cereal grains, and dark green vegetables are good sources of calcium as well, but milk generally has a higher calcium content compared to these options.

Correct Answer: A

Rationale: The correct answer is Vitamin B12. Vitamin B12 is primarily found in animal products, so individuals following a vegan diet are at risk of deficiency as they do not consume these sources. Vitamin C, Carbohydrates, and Fiber are not specifically at risk for deficiency in vegan diets as they can be obtained from plant-based sources.