Correct Answer: D

Rationale: Eggs are considered a source of complete protein because they contain all the essential amino acids required by the body. The other options, cereal grains, beans, and nuts, do not provide all the essential amino acids in the necessary proportions to be classified as complete proteins.

Correct Answer: A

Rationale: The correct answer is A: monosaccharides. When macronutrients like carbohydrates are digested, they are broken down into simpler forms. Carbohydrates are broken down into monosaccharides, proteins into amino acids, and fats into fatty acids. Therefore, the end products of carbohydrate digestion are monosaccharides. Choices B, C, and D are incorrect because polysaccharides are larger carbohydrate molecules, enzymes are not the end products of digestion but rather aid in the process, and cholesterol is not a direct end product of macronutrient digestion.

Correct Answer: A

Rationale: The correct answer is A: bile. Bile acts as an emulsifier, breaking down fats into smaller droplets to aid in digestion and absorption. Trypsin is a digestive enzyme that acts on proteins, not fats. Lipase is an enzyme that breaks down fats, but it doesn't act as an emulsifier. Cholecystokinin (CCK) is a hormone that stimulates the release of digestive enzymes, including lipase, but it is not directly involved in emulsification.

Correct Answer: A

Rationale: The correct answer is A: Smelling or seeing food. When an individual smells or sees food, it can trigger the body to start producing digestive secretions in anticipation of food consumption. This physiological response helps prepare the digestive system for the incoming meal. Choices B, C, and D are incorrect because grocery shopping, fasting, and exercise do not directly stimulate digestive secretions in the same way that the sight or smell of food does.

Correct Answer: D

Rationale: Eggs are considered a source of complete protein because they contain all the essential amino acids required by the body. The other options, cereal grains, beans, and nuts, do not provide all the essential amino acids in the necessary proportions to be classified as complete proteins.