Correct Answer: B

Rationale: The correct answer is B: Cough drops. Patients with COPD often use cough drops to manage their symptoms, which can lead to an increase in carious lesions due to their sugar content. Choices A, C, and D are incorrect as protein, fluoride, and xylitol are not typically associated with an increased risk of carious lesions in patients with COPD.

Correct Answer: A

Rationale: The correct answer is an ionic bond. An ionic bond is formed when a positively charged metal ion joins with a negatively charged nonmetal ion, resulting in a transfer of electrons. In contrast, a covalent bond involves sharing electrons between atoms rather than complete transfer. Functional groups are specific groups of atoms within molecules that determine the molecule's chemical properties. Metallic bonds occur between metal atoms where electrons are shared across a delocalized electron cloud.

Correct Answer: A

Rationale: Oliguria, or reduced urine output, is often the initial major sign of acute renal failure. This reduction in urine output indicates that the kidneys are not functioning properly. Hematuria (blood in urine), proteinuria (presence of protein in urine), and glycosuria (presence of glucose in urine) are not typically the initial major signs of acute renal failure. While they may be present in certain conditions, oliguria is the most common and critical indicator of acute renal failure.

Correct Answer: B

Rationale: The correct answer is B, 'Hypogeusia.' Hypogeusia refers to a diminished sense of taste, which can impact nutritional intake, especially in older adults. Xerostomia (choice A) is dry mouth, Dysphagia (choice C) is difficulty swallowing, and Anosmia (choice D) is the loss of the sense of smell. These conditions are different from loss of taste, making them incorrect choices for this question.

Correct Answer: B

Rationale: The small intestine is the correct answer. It is the primary site for nutrient digestion and absorption in the digestive system. The small intestine plays a crucial role in breaking down carbohydrates, proteins, and fats into forms that can be absorbed by the body. While the large intestine absorbs water and electrolytes, the majority of nutrient absorption occurs in the small intestine. The stomach primarily functions in the initial digestion of proteins, and the mouth begins the mechanical breakdown of food through chewing.