Correct Answer: C

Rationale: Scurvy is caused by a deficiency of vitamin C, not vitamin E. The symptoms of scurvy include spontaneous gingival hemorrhaging, perifollicular petechiae, follicular hyperkeratosis, diarrhea, fatigue, depression, and cessation of bone growth. Vitamin A (Choice A) is important for vision and immune function, Vitamin D (Choice B) is essential for bone health, and Vitamin K (Choice D) is necessary for blood clotting. However, none of these vitamins are associated with scurvy.

Correct Answer: B

Rationale: The correct answer is B: Iron. The provided extract mentions that iodine deficiency can cause delayed tooth eruption, enlarged tongue, stillbirths, altered craniofacial growth, sensitivity to cold, dry skin, depression, and goiter. Zinc, Sodium, and Potassium are not associated with these specific symptoms. Zinc deficiency can lead to other health issues but not the ones mentioned. Sodium and Potassium imbalances do not typically result in the symptoms described in the question.

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: C

Rationale: The statement is correct, but the reason is not correct. A major difference between fat-soluble and water-soluble vitamins is that the body is able to store larger amounts of fat-soluble vitamins. Vitamins A and D are stored for long periods; therefore, minor shortages might not be identified until drastic depletion has occurred. Observable signs and symptoms of a dietary deficiency are often not identified until they are in an advanced state. Water-soluble vitamins, on the other hand, are not stored in the body and are excreted in the urine if taken in excess, making it harder to reach toxic levels.

Correct Answer: D

Rationale: Total kilocalories have the greatest effect on body weight as they represent the overall energy intake from all macronutrients combined. While the consumption of specific macronutrients like carbohydrates, proteins, and fats can affect weight management, the total calories consumed play the most significant role in determining body weight. Therefore, choices A, B, and C are incorrect as they focus on individual macronutrients rather than the overall energy balance provided by total kilocalories.