The major focus of nutritional recommendations in this century has shifted to:

Correct Answer: A

Rationale: The correct answer is A: prevention and control of chronic diseases. In this century, nutritional recommendations have increasingly emphasized the importance of preventing and managing chronic diseases like obesity, diabetes, cardiovascular diseases, and cancer. Lifestyle factors such as diet play a significant role in the development of these conditions. Option B, improved sanitation and public health, although important for overall health, is not the primary focus of nutritional recommendations. Option C, prevention and control of infectious diseases, is also crucial but does not reflect the current major focus of nutritional recommendations. Option D, development of healthful foods using food technology, is a valid area of interest but is not the primary shift in focus observed in nutritional recommendations.

Correct Answer: B

Rationale: The correct answer is B: nutrition science. Nutrition science specifically focuses on studying the requirements and functions of nutrients in relation to human growth, maintenance, activity, and reproduction. Choice A, physiology, deals more with the functions of living organisms and their parts, not specifically related to nutrients. Choice C, biochemistry, focuses on the chemical processes and substances that occur within living organisms, not specifically centered on nutritional requirements. Choice D, dietetics, involves the application of nutritional knowledge in planning and managing diets for individuals, but it is more focused on the practical aspect rather than the broader scientific study of nutritional requirements.

Correct Answer: D

Rationale: The correct answer is D: registered dietitian. A registered dietitian is a healthcare professional with specialized training in nutrition and dietetics, making them primarily responsible for applying nutrition science in clinical practice settings. Nurses (choice A) and physicians (choice B) may have some knowledge of nutrition, but a registered dietitian has specific expertise in this area. Public health nutritionists (choice C) typically focus on community nutrition and public health programs, rather than clinical practice settings.

Correct Answer: C

Rationale: Public health nutritionists work within communities to ensure that populations have access to nutritional resources. They focus on promoting good nutrition, developing programs, and educating the public about healthy eating habits. While community physicians, public health nurses, and registered dietitians may also play roles in promoting nutrition in the community, the primary responsibility for nutrition care typically falls under the purview of public health nutritionists.

Correct Answer: B

Rationale: A variety of foods is the best source of nutrients because it ensures a balanced intake of all essential nutrients required by the body. Option A, specific food combinations, may not provide all necessary nutrients as relying on only a few types of food may lead to deficiencies. Option C, individual foods, also may not provide a complete range of nutrients necessary for overall health. Option D, a variety of food supplements, is not the best source of nutrients as whole foods are generally more beneficial due to their natural nutrient composition and bioavailability.