Correct Answer: C

Rationale: The correct answer is C because drinking hot chocolate before bed contains caffeine which can disrupt sleep. A is correct as exercise can promote better sleep. B is correct as smoking can affect sleep quality. D is correct as reading before bed can help relax the mind.

Correct Answer: C

Rationale: The correct answer is C because life expectancy is influenced by multiple factors such as gender, ethnicity, and living environment. Gender does play a role, but it is not the sole determinant. Ethnicity and living environment also significantly impact life expectancy. Genetic factors may contribute, but they are not the primary factor affecting life expectancy. Therefore, choice C is the most comprehensive and accurate statement. Choices A and B are incorrect as they oversimplify the factors that influence life expectancy, while choice D is also incorrect as it overlooks the significant impact of other factors beyond genetics.

Correct Answer: C

Rationale: The correct answer is C: Medications and polypharmacy. In older adults, incontinence is commonly caused by medications that affect bladder control, such as diuretics, sedatives, and anticholinergics. Polypharmacy can worsen this by increasing the likelihood of drug interactions. Chronic urinary tract infections (A) can cause incontinence but are less common in older adults. Neurological disorders (B) like dementia or stroke can also lead to incontinence but are not the most common cause. Poor hydration (D) can exacerbate incontinence but is not the primary cause.

Correct Answer: D

Rationale: The correct answer is D: Serum triiodothyronine (T3) and gastric pepsin. Aging typically leads to a decrease in serum T3 levels due to reduced thyroid function. Gastric pepsin production also decreases with age, impacting digestion. A: Creatinine clearance and insulin secretion typically decrease with kidney and pancreatic function decline, not necessarily solely due to aging. B: Blood CO2 levels and saliva production are not directly affected by aging but can be influenced by various health conditions. C: Left ventricle-wall thickness may increase with age due to conditions like hypertension, and skin healing time can be affected by various factors other than just aging. In summary, the correct answer stands out as age-related declines in serum T3 and gastric pepsin levels are more directly linked to the aging process compared to the other choices.

Correct Answer: C

Rationale: The correct answer is C because it states that the exact cause of super-centenarians' longevity and good health is not known. This acknowledges the uncertainty and complexity of the situation, highlighting the need for further research and understanding. Explanation for why the other choices are incorrect: A: Genetic makeup alone may not fully explain super-centenarians' survival, as there are likely additional factors involved. B: Living in wealthier areas does not guarantee longevity or good health, as there are many other factors at play. D: While quality medical care and improved social conditions can contribute to health, they are not the sole reasons for super-centenarians' exceptional longevity.