Correct Answer: D

Rationale: The correct answer is D because increasing medications would not directly address xerostomia. Xerostomia is dry mouth, often caused by decreased saliva production. Using humidifiers (A) helps increase moisture in the air, mouth rinses/artificial saliva (B) lubricate the mouth, and sugar-free hard candies (C) stimulate saliva production. Increasing medications (D) would not target the root cause of xerostomia and may even exacerbate dry mouth symptoms.

Correct Answer: B

Rationale: The correct answer is B because limited physical activity and poor nutrition have been consistently linked to cognitive decline in older adults. Physical activity promotes blood flow to the brain, which helps with cognitive function. Additionally, a balanced diet rich in nutrients supports brain health. Genetic predisposition (A) can play a role but is not the most closely associated factor. Social engagement and mental stimulation (C) are beneficial for cognitive health but not the primary factor for decline. Early retirement and lack of work-related stress (D) are not directly linked to cognitive decline.

Correct Answer: A

Rationale: The correct answer is A: Alzheimer's disease. It is the most common type of dementia in older adults, accounting for around 60-80% of cases. Alzheimer's is characterized by the presence of beta-amyloid plaques and tau protein tangles in the brain, leading to memory loss and cognitive decline. Vascular dementia (B) is caused by impaired blood flow to the brain, Lewy body dementia (C) is characterized by abnormal protein deposits in the brain, and Frontotemporal dementia (D) affects the frontal and temporal lobes of the brain, leading to changes in behavior and personality. However, in older adults, Alzheimer's disease is the most prevalent form of dementia due to its widespread impact on memory and cognition.

Correct Answer: B

Rationale: Loneliness in older adults can lead to increased stress, inflammation, and unhealthy behaviors, all of which can elevate the risk of cardiovascular disease and depression. Social isolation can also impact mental health. Choice A is incorrect as loneliness does impact health. Choice C is incorrect as loneliness typically weakens immune function. Choice D is incorrect as loneliness affects both mental and physical health.

Correct Answer: B

Rationale: The correct answer is B: Thyroid gland. The thyroid gland produces hormones that regulate metabolism. In older adults, decreased thyroid function, known as hypothyroidism, can lead to a decrease in metabolism. This can result in symptoms such as fatigue, weight gain, and slowed heart rate. A: Kidney - While the kidneys play a role in filtering waste and maintaining fluid balance, decreased kidney function typically does not directly impact metabolism. C: Brain - The brain plays a crucial role in regulating various bodily functions, but it does not directly control metabolism. D: Skeleton - The skeleton provides structural support and protects organs but does not directly influence metabolism.