Correct Answer: C

Rationale: Adolescence is the most critical stage for building bone mass, which plays a significant role in preventing osteoporosis in later life. During adolescence, approximately 45% of adult bone mass is formed. Although bone mass can be built during infancy, early childhood, and young adulthood, it is not as significant as during adolescence, making choices A, B, and D incorrect. Therefore, focusing on adequate nutrition and physical activity during adolescence is vital for long-term bone health.

Correct Answer: D

Rationale: In type 1 diabetes, the body's immune system destroys the beta cells in the pancreas that produce insulin. This leads to an insufficient amount of insulin, which is required to facilitate the transport of glucose into the cells. Consequently, blood glucose levels remain high. The other options are incorrect. Option A is incorrect because urinary excretion of glucose does not directly contribute to blood glucose levels. Option B is incorrect because, while gluconeogenesis does produce glucose, it is not the cause of high glucose levels in type 1 diabetes. Option C is incorrect because absorption efficiency of glucose from the gastrointestinal tract does not affect the amount of insulin available to transport glucose into cells.

Correct Answer: D

Rationale: The correct answer is D, 'Consume small, frequent meals when hunger strikes.' This strategy is ideal for managing morning sickness because it prevents the stomach from becoming too empty, which can exacerbate nausea. Option A may not be helpful because dairy products can sometimes worsen nausea. Option B is not the most effective solution as the sitting position does not directly impact nausea levels. Option C, while generally beneficial for digestion and overall health, does not specifically address the issue of pregnancy-related nausea.

Correct Answer: D

Rationale: The correct answer is phosphorus. Retention of phosphorus in patients with Chronic Kidney Disease (CKD) contributes to the development of bone disorders, including osteodystrophy, because it disrupts the balance of calcium and phosphorus in the body. This imbalance leads to a variety of bone diseases. The other options - iron, sodium, and potassium - while important in the overall metabolic function, are not directly linked to the development of bone diseases in CKD patients due to retention.

Correct Answer: B

Rationale: This scenario illustrates depression or social isolation as a risk factor for malnutrition. After the death of his wife, the elderly man may have experienced depression or social isolation, which can lead to decreased food intake and poor nutritional status. Although age, chronic illness, and impaired mobility can also contribute to malnutrition, they are not the primary factors described in this scenario. The history of chronic illness (Choice A) and impaired mobility (Choice D) were not mentioned in the scenario, and while age (Choice C) is a factor, it's not the main factor depicted in this case.