Correct Answer: B

Rationale: Iron is an essential nutrient for the body, and while it can be found in many different types of foods, the amounts can vary significantly. Cheese, while a good source of other nutrients like calcium and protein, is not a particularly rich source of iron. On the other hand, clams, legumes, and dried fruits are known to contain higher levels of iron. Therefore, among the provided choices, cheese is considered a poor source of iron. It's important to note that a balanced diet should include a variety of foods to ensure the intake of all necessary nutrients.

Correct Answer: B

Rationale: The correct answer is B: Breast. Lactose is synthesized in the breast during lactation to produce breastmilk. The liver is responsible for various metabolic functions but does not synthesize lactose. The kidney's primary role is in filtering blood and regulating electrolytes, not lactose synthesis. The pancreas is involved in producing digestive enzymes and insulin, not lactose synthesis.

Correct Answer: B

Rationale: It is false that the major determinant of a person's total cholesterol levels is the amount of cholesterol in their diet. While dietary cholesterol can have some impact on total cholesterol levels, it is not the major determinant. The amount and types of fats consumed, particularly saturated and trans fats, have a more significant impact on blood cholesterol levels. Therefore, a diet high in these types of fats can lead to high cholesterol, irrespective of the amount of dietary cholesterol consumed. This is why it is essential to maintain a balanced diet with a limited intake of saturated and trans fats.

Correct Answer: C

Rationale: The correct answer is 'health care agent.' A health care agent is appointed through a durable power of attorney to make medical decisions on behalf of a patient who becomes incapacitated. The term 'witness' (choice A) is incorrect because a witness only observes the signing of the directive and does not make decisions. 'Primary caregiver' (choice B) is also incorrect as they may provide care but are not necessarily legally empowered to make decisions. 'State proxy' (choice D) is not commonly used in the context of advance directives or health care decision making, making it an incorrect choice.

Correct Answer: B

Rationale: People with phenylketonuria should avoid aspartame because it contains phenylalanine, which they cannot metabolize. Acesulfame-K, saccharin, and sucralose do not contain phenylalanine and are safe for individuals with phenylketonuria. Therefore, the correct answer is B. Acesulfame-K, saccharin, and sucralose are incorrect choices because they do not pose a risk for individuals with phenylketonuria due to the absence of phenylalanine in their composition.