Correct Answer: D

Rationale: The correct answer is choice D because medication for high cholesterol is typically not considered unless Therapeutic Lifestyle Changes (TLC), which include diet and exercise, have not proven effective after a three-month period. This approach ensures that lifestyle modifications are given a fair chance to lower cholesterol levels before resorting to medication. Choice A is incorrect because the number of risk factors for coronary heart disease does not dictate when to begin medication; it is about the effectiveness of lifestyle changes. Choice B is incorrect as the duration of coronary heart disease symptoms does not determine when to start medication; the focus is on the response to TLC. Choice C is incorrect because the coverage of prescription drugs by the patient's insurance does not influence the medical decision to use medication for high cholesterol; it is based on medical necessity and effectiveness of prior interventions.

Correct Answer: D

Rationale: The Dietary Reference Intake (DRI) for protein is primarily determined by an individual's body weight. This is because the body's protein requirement is proportionate to its size, which is generally reflected in the body weight. Therefore, choice D is correct. Choices A, B, and C are incorrect: While factors such as fatty acid intake, gender, and height can influence an individual's overall nutritional needs, they do not directly determine the DRI for protein.

Correct Answer: B

Rationale: The correct answer is B: Essential fatty acids are not manufactured by the body. These fatty acids must be obtained through the diet because the body cannot synthesize them. Choice A is incorrect because essential fatty acids can come from both animal and plant sources, not just from an animal source. Choice C is the correct characteristic of essential fatty acids. Choice D is incorrect because essential fatty acids are not produced by the body.

Correct Answer: A

Rationale: The most likely nutrition-related side effect after head and neck surgery for cancer treatment is aspiration. This is due to changes in swallowing mechanics, which can cause food or liquids to be inhaled into the lungs. While acid reflux, dumping syndrome, and diarrhea are potential side effects related to nutrition, they are not as directly connected to head and neck surgery. Acid reflux is more often related to issues with the lower esophageal sphincter, dumping syndrome is typically a complication of gastric surgery, and diarrhea can have various causes, including certain medications or gastrointestinal illnesses.

Correct Answer: A

Rationale: Carbohydrates are composed of carbon, hydrogen, and oxygen. These three elements combine to form the basic structure of carbohydrates. Oxygen is an essential element in carbohydrates, contributing to their chemical composition. Choice B (nitrogen) is incorrect as nitrogen is not a typical component of carbohydrates. Choice C (water) is incorrect as water is not an element but a compound composed of hydrogen and oxygen. Choice D (glucose) is incorrect as glucose is a specific type of sugar, not an element found in the composition of carbohydrates.