Symptoms of irritable bowel syndrome are most likely associated with disturbed defecation, bloating, and _____.

Correct Answer: B

Rationale: Abdominal pain is a common symptom of irritable bowel syndrome (IBS), along with bloating and changes in bowel habits. Rectal bleeding (choice A) is more commonly associated with conditions like inflammatory bowel disease or colorectal cancer. Rectal fissures (choice C) may cause rectal bleeding but are not typically considered a core symptom of IBS. Esophageal paralysis (choice D) is unrelated to the symptoms of IBS, which primarily affect the lower gastrointestinal tract.

Correct Answer: B

Rationale: Reduced stomach acidity impairs the absorption of iron, as an acidic environment is necessary for optimal iron absorption in the stomach. Choices A, C, and D are incorrect as medications that reduce stomach acidity typically do not significantly affect the absorption of calcium, vitamin D, or vitamin C.

Correct Answer: A

Rationale: Reduced salivary output is a common physical change in aging. This can affect an older adult's nutrition by impacting chewing, swallowing, and taste perception. The decrease in saliva production can make it harder to chew and swallow food effectively, affecting the overall eating experience. Additionally, saliva plays a role in taste perception, so a reduction in salivary output can lead to alterations in how food tastes, potentially impacting an individual's appetite and food choices. Increased gastrointestinal motility (choice B) is not typically associated with aging and would not directly affect nutrition. Abnormal cortisol production (choice C) is related to hormonal changes and is not a common physical change of aging that affects nutrition. An increase in the number of taste buds (choice D) is not a typical change associated with aging and would not have a significant impact on an older adult's nutrition.

Correct Answer: B

Rationale: The correct answer is B because many teens regularly consume energy drinks, which can contribute to poor nutritional health due to their high sugar and caffeine content, leading to unhealthy dietary patterns. Choice A is incorrect because choosing fruit juice and milk over soda would generally be considered a healthier choice. Choice C is incorrect as busy schedules leading to inadequate fluid intake might impact hydration but not necessarily poor nutritional health. Choice D is also incorrect as consuming low-fat milk is not typically a significant factor contributing to poor nutritional health among adolescents.

Correct Answer: B

Rationale: The correct answer is B, contracting the uterus. Breastfeeding helps contract the uterus after childbirth, reducing postpartum bleeding and helping the uterus return to its pre-pregnancy size more quickly. Choices A, C, and D are incorrect because conserving calcium stores, protecting against future hypertension, and speeding the resumption of ovulation are not direct benefits of breastfeeding to the mother.